Big Barbeque HowTo for Techies
Too busy to blog!
I stopped blogging for quite a few weeks now. Just too busy to even get my head out of work mostly. I was one of the lead organizers for an annual internal technical training and conference and headed up IT, registration, audio/visual and food for the week-long event. Our group of about 200 people worldwide has undergone some major changes in the last few months. A complete re-organization. All new VP, Sr. Director, and Director that I report to now. I'm in a new position too, doing similar techie stuff, but under a slightly different charter and for slightly different vertical market segments. Morale was pretty mixed at the beginning. But people seem to have cheered up after the conference where they all had a chance to enjoy a few cold drinks and some good food. I must say that the week long event couldn't have been a more perfect venue. We had speakers like Andy Bechtolscheim, Scott, and Jonathan do keynotes for us. And they didn't disappoint. I felt it a personal duty to serve food that was at least worthy of such a great program.
Hosting a week long event can be tough. We had great help from our organizing committee. Content was led by Matthias, a German colleague out of Sun's Walldorf office. And logistics for budget and travel were handled by logistics expert, Don. He pretty much shaved travel, lodging, and ground transportation costs down to around than $1000 per person for the roughly half the participants coming from 13 other countries and 5 major areas around the US. As we all know, budgets can be tight, and directors are given very limited dollars for group team events these days. Times were more encouraging this quarter because those funds were more available. But still, the overarching directive was still to watch our costs. Still, I actually had the opportunity to lead 2 major events - a BBQ and a Luncheon and act as primary cook for a third (Fajitas & 'Ritas). The Fajitas and Margaritas party and the luncheon were employee funded with minor support from the company, while the BBQ in the park was picked up completely by the company. The costs? Well, the Wednesday BBQ for 160 people cost just under $5/person. The Thursday Fajitas and 'Ritas (Margaritas) Party for 69 people cost about $5 - $10 each depending on whether a participant imbibed, and the Friday luncheon for 180 was just $3/person.
Catering to my Colleagues
First of all, I love to cook for people and I love to grill. It goes back to my academic history. I was pretty active in student societies back at Cal Berkeley. In my senior and 1st grad school years, I was BBQ'ing almost 3 times a week for various student groups. These were mostly morale/team building events that were revenue neutral. But the joke in the College of Engineering was that I was the master of porous media Heat Transfer - the porous media being charcoal briquettes, real wood, or fake crushed volcanic stuff over a propane fueled flame. There was just something about grilling outdoors that put me in touch with my primal roots. Beat the tom-tom drum. Sing Kumbaya kinda stuff. Bond with nature, yadi yadi yadi.
Wednesday Afternoon BBQ
Getting back to the Wednesday BBQ. There are lots of ways to cater a large outdoor BBQ party, but quality and quantity can vary drastically depending on the help, menu and venue. And I can't overlook good help. Some of our group admins have tremendous logistical experience with events and they showed up and helped out. Our of our stars, Kim, is 8 months pregnant (almost 9 now) and she showed up early with 80lbs of ice! We also had 3 engineers show up early and post signs along the roads and park to guide folks to our destination, plus setup the chow lines and place all the food for optimum parallel processing of hungry eaters as they came through. The Directors showed up and ran all the slice-n-dice food prep operations for hors d'oeuvres and other items. It was real team work.
But for the best help, my recommendation would be tough for anyone else to follow, because I would suggest that you marry a spouse as helpful as my wife. She really pitched in with the shopping and the food prep. We were both up late the night before, first shopping and then prepping and marinating, and then up again at 4:30 am in the morning before the BBQ to prep some more, cook some of the dishes and load up the vehicles, etc.
BBQ Risk Management
The way I organize a BBQ is all about risk management. There's environmental risk, like the weather not cooperating. And there is operational risk. Certain operations can be delegated, like setup and cleanup. But some operations, like procurement, must be controlled by and given to a single party or we risk having the standard asyncronous potluck syndrome - too much beer, chips, cake and spoons, but no plates, forks, diet beverages and main dishes. Then there's the health risk. One challenge here is sanitation. Another challenge is storage. How many folks can handle literally 1000 lbs of liquid and then deliver it the day of the event? What about a hundred pounds of raw meat? How many folks have food-service experience? While the risk of e.coli and salmonella contamination are fairly low, with a company event, 200 high-IQ engineers could be made pretty unproductive for quite some time if some outbreak should occur. Having worked in a restaurant for 4.5 years and done lots of procurement, usually, that's a job I take personal responsibility for. This leaves Menu and Venue left as action items for others to decide.
A Possible Menu
Planning an event is almost like doing Product Life Cycle (PLC) Management, only the time frame is a lot shorter. You have an approval committee that has managers and architects, and multiple people are tasked with action items (in our case - a BBQ Event) and we draft half-pagers and one-pagers outlining our proposed Architecture or Menu. Cost/Benefit ratios are analyzed, small separate committees and product teams (cTeams and pTeams) form around separate tasks and we set milestones. As milestones come and go, we track progress, and finally, come GA, people pull all nighters to make sure stuff ships on time. In our case, it all started with my proposed menu. Since I took responsibility for procurement, the group thought it only appropriate to give me the privilege of doing the menu (not to mention it would save a lot of hassles all around to just have me do it.)
For openers, I was planning on smoke salmon on french baguette slices with olive oil, pickled capers and dill weed. A classic hors d'oeuvre, but somewhat labour intensive. Others suggested that we simplify and modify this and provide individual bags of variety Chips - a la Frito Lay-style. We thought about this and it was decided that we do both. The Directors we given the assignment to fabricate the smoked salmon hors d'oeuvres and they did an okay job, although they skimped on the smoked salmon and only used up one pack of salmon and left about 2 baguettes. The next step was to provide some first course (Prima Piatti) options. Usually, in the states, this means salad. We decided to offer a tossed mixed salad (insalate miste) but with a Ranch dressing and small tiny olive tomatoes plus optional Potato salad. Both are extremely affordable and come mostly pre-packaged off-the-shelf. Next was to provide a Carbohydrate option prior to or with the main (second) course. We considered the sensitivity to all the Vegetarians and came up with two optional items. Garlic Bread Forte (strong garlic bread - Bamm!! with like lots o' Garlic), sweet dinner rolls (for folks with the Vampire retro virus - intolerant of garlic), steamed Basmati rice seasoned with Tumeric, Saffron, Cardamom and Raisins, and lastly, spaghetti with a simple marinara sauce. The main course would be an assortment of grilled boneless beef rib steak and boneless dry rub seared chicken thigh meet, italian sausage and Cajun style Hot Links and Portabella Mushroom Burgers. For desert, we planned for any bulk bags of seasonal fruit like apples and oranges. And finally, for drinks, we went with a full non-alcoholic beverage list of all individually bottled or canned sodas, diet sodas, sparkling water and plain bottled water sans gas.
Note on Vegetarians/Vegans
Vegetarians are categorized as folks who do not eat meat, but may eat eggs, cheese and other diary products. Vegans do not eat any animal products whatsoever. In any high tech company doing software these days, you can expect about 30% of the people to eat vegetarian-only and a small 1% or so to be Vegan. These are mostly the Indian engineers, and we need consider their needs as well. This means purchasing 100% durum wheat pasta (no eggs) or making a number of traditional rice and lentils dishes that do not contain butter, milk or eggs. And in some cases where stock is required in a sauce reduction, we need to use vegetable stock only. Since such dishes can be appealing to both meat eaters and vegetarians, it's important to make enough for everyone. That gets a bit tricky sometimes because some dishes may be labour intensive or costly and thus limited. For example, 2 years ago, at previous BBQ, I had a stack of portabello mushroom burger/steaks simmering in a marsala wine gravy that was enough for 30 or so vegetarians. But the mainstream folks loved them so much, it got depleted in less than 3 minutes and so quite a few vegetarians went without their main course. It still bothers me that I didn't prepare for that outcome and some folks went hungry. The obvious response by the omnivores was a bit callous - "It's BBQ Darwinism - Omnivores rule!"
This year, we chose to host this event at Sunnyvale Baylands Park - a municipal park that was both nearby and reservable for a fee. Another good thing was that this park had defined hours when they opened and closed, and charged all persons for parking. Such parks are usually fairly reasonable venues, costing just $300-$500 for site reservations, and discounted parking for groups on the order of $3/vehicle. By carpooling, the parking fees can be further reduced. We could have found a cheaper venue for sure that was only $50 to reserve and had free parking. But we chose the paid route this year for several reasons. The first is that the fees help to maintain the park in optimal condition. Free public parks tend to be more run down and lack clean facilities like bathrooms, electrical power and potable water. Second is that the defined hours and cost inhibit transients - especially the mentally unstable - from taking up residence in the park. Last year, when we hosted a previous BBQ in Milpitas, I ended up having to call Police when a young man in his early 20's on a BMX bicycle decided to crash the party. He began reaching down into his pants in front of a group of us, including our V.P. We've learned since then to be more selective about venues.
Make no mistake that in a BBQ, the key to cooking is mastering the Fire. The type of flame one targets really depends on the type and size of the BBQ. Typically, public parks have two types of BBQs. For single family and small picnics, they have a small metal box welded on top of a pedestal. It has a 1/2 sq. meter grilling surface and slots on the sides that allow the grill height to be adjusted. For larger group BBQs, many parks have masonry pits. These are often about 2 sq. meter area rectagular pits recessed inside a waste high masonry structure. A heavy wire mesh screen on a chain and pulley allow the entire grill to be raised or lowered over the pit via a long crank handle or cog wheel.
I know some folks who bypass public BBQ pits and lug their own grills because the public units are either broken or filthy. While this is sometimes necessary, often, a stiff wire grill brush plus a very hot fire are enough to rejuvenate even the most gnarly of public grills. Fortunately for us, the Pits at Sunnyvale Baylands are in premium condition. They are the big rectangular recessed pit types and each have potable water on one side of the grill and an electrical outlet with 110 VAC power on the other. Each reservable area sports 5 such pits and its own prep table, picnic tables, and garbage and recycling receptacles. Truly one of the finest public parks facilities I've had the privilege to cook at.
For public pit BBQs, I use a 3 stage fire that takes about 35 - 45 minutes to get ready. It starts with a modest amount of charcoal briquettes on the bottom. Any brand will do. I only use this as catalyst to pre-heat the pit. About 5 lbs shaped into a conical mound works for small pits. About 20 lbs (10kg) are more appropriate for the large pits. Note that the mound should be shifted over to one side of the grill. Which side? Well, take a sense of the wind direction and observe over a few minutes. Then position yourself on the side of the pit where statistically the wind is mostly at your back. This is critical when you cook so fumes from the smoke don't overwhelm you. For right handers, the main fire should be primarily on your right. Raw food starts on this side, and as it cooks, you flip it and move it to the left. Lefties should start fires on the left side. Don't worry if you don't cover the entire pit. You only need about 1 sq. meter of cooking surface per 75 people or so. You want some areas without direct heat underneath for food warming purposes but not cooking.
Next, squeeze a generous amount of charcoal lighter on the mound of briquettes. About 25cc/kg (about 0.4 fl. oz per pound of briquettes). Let it soak into the coals. Then light the fire. Wait about ten minutes and when the primary fuel has burned off, toss about twice equivalent weight of mesquite chips on top of the charcoal. If you like, you could switch and mix 50% mequite, and 50% hickory chips. You can buy BBQ chips from most BBQ supply places. Walmart has this near the garden section in 18lb bags. The key is to get blocks of chips that are about 5 cm in largest dimension but no smaller than 2.5 cm in smallest dimension. Technically these would be more like blocks than chips. Tossing the chips on the coals can snuff the flames out or reduce the flames initially. Don't worry, if the charcoal has been ignited properly as per the instructions above, it will reignite the chips in due time. If you're in a hurry and need to accelerate the process, get a piece of cardboard or a large, stiff paper plate and fan the coals for a few minutes to get oxygen into the center. This makes the coals red hot and when you stop, you should see a light blue flame shoot up as the adiabatic flame temperature really hits the 500 deg C mark the chips ignite readily.
Note that on rainy days where the humidity is in the high 90 - 100%, BBQs are very hard to light and start. Increase the fuel amount, and protect the coals and wood from getting damp. This is critical or else you make need to take much longer to fire up the coals. If rain is coming down, well, hopefully, you had a contigency plan to cater the food indoors and bake or broil the items in an oven. (But it doesn't rain often in October in California. We had 26 deg C weather most of that day. Just fantastic.)
Once the wood chips are burning well, which should be about 10 minutes later, take a fireplace poker or long sacrificial stick and spreadout the coals and chips more evenly. I then place oak or almond hardwood logs on top of the coals and let these catch fire. Again, about 2 or 3 times the amount of original charcoal by volume. I let this burn about 10 minutes more, until more than half the surface of the logs are white charred and glowing. It's now time to lower the grill above the fire. You should feel a tremendous amount of heat rising up as you get close, since the walls of the pit effectively insulate all heat loss from the side, all the heat is directed up. The heat may be unbearable. Usually, if I reach over quickly, just above the pit, the tips of the hairs on the back of my hands and forearms will burn. I highly recommend at this time to you have a small 2 - 5 gallon buck next to you, filled with cold fresh water for keeping your hands and arms moist. The evaporation of water will protect the skin up to 15 seconds as you reach over to manipulate food. But once your skin goes dry, you can receive 2nd degree burns easily roasting your hand and arm over the fire.
Note: For our event with 160 guests on the RSVP list, we expect about 15% more party crashers (because of the free food and proximity to our Santa Clara Campus). To accomodate such a large crowd, we decided on two pits to double the cooking surface. This also made sense since would could now toast a lot of vegetarian items on one grill with one set of utensils without fear of cross-contamination with meat and/or meat juices from the other grill.
Cooling down the drinks
Initially, such a fierce fire is not really suitable for cooking. Food would char instantly and the inside would still be raw. However, this heat is great for sterilizing and carbonizing any deposits on the grill. I usually let the heat do its job at this time and come back later with wet hands and a stiff wire brush to clean it before putting on my first items. Around this time, I prepare drinks, a thankful task because it gets me away from the pit and doing something that involves cold ice.
Lots of people think that with BBQs, the biggest task is the preparation and cooking of meat items. In fact, that's probably not true. If you deal with 18 - 29 year olds, the average male will eat only about 3/4 pound of meat (wt. before cooking) at any BBQ. Females eat just under 1/3 rd pound of meat. For the group 30 - 45 years of age with , reduce both down by 33%. That means for a group with average age of 32 years and 3/4ths males, and 1/4th females, we can expect 200 people to eat less 100 lbs of meat type items.
However, if the weather is warm, which it was 3 weeks ago - you can expect each male to consume close to 2.0 liters of liquid during a 5 hour period. Not all of it is actually swallowed, but people tend to waste about 25% of their beverages because they don't finish it before getting a new one, or they confuse it with someone else's beverage and then don't want to drink it. So on a hot day, we need to haul a lot of drinks. And the amount could even be more if most folks decide to participate in any physical activities like soccer (football), frisbee golf, etc. For 200 persons, this means having about 5 lbs of liquid each or about 1000 lbs of drinks. Try hauling that in a normal vehicle or minivan. It's quite difficult. And for most employees, such a monumental undertaking of hauling 1000 lbs of liquid is just not practical. That's where my wife and I come in. I drive a small Toyota Pickup. She drives a Sienna minivan. Between the two of us, we can haul about 1 tonne. This is sufficient for most warm weather BBQs upto 200 persons.
I still haven't gotten down to describing how to cool down the drinks. And this is a logistical trick. Basically, in warm weather, ice melts quickly. And it takes up volume so it's difficult to store. The key therefore, is to buy the Ice the morning you plan to use it. Or better yet, if someone on the team has an Uncle that owns the largest west coast Ice distribution company, even better. In fact, Kim, our expectant admin has an Uncle who has an Ice company, and we were able to get high quality (i.e. very cold and small chipped) ice in large quantities, and we could get it shipped to our site at exactly 11am prior to 12:30pm serving time. We needed a total of about 100 lbs of ice for the afternoon to chill about 1000 lbs of drinks.
With 3 bushel-sized large plastic drink tubs and two large capacity ice chests, we were able to load about 1/2 of all the drinks loosely into the tubs and put about 2/3rds of the ice into the ice chest. We then took ice bags and spread the ice over the drinks. The solid-to-solid contact of ice to beverages has very low rate of thermal diffusion and low Nusselt number. Such a tactic would take 2 hours to chill down drinks. To reduce time down to 15 minutes, a trick we heat transfer guys use is the 0.4 deg C triple point for water/ice/vapour mixtures. Basically, you can be assured that if you have a water/ice slurry, the temperature of the water will remain pretty close to 0.4 deg C as long as solid ice is still present. A beverage in contact over its entire surface with such a cool slurry will cool down to just 5 deg C (frige temp) in just 15 minutes or less. So the key is to add water to the tubs to immerse most of the drinks and then pile on the ice and somewhat fold it into the water to make a slurry. The Nusselt number goes way up as the liquid water not only increase surface area, but provides a fluid for much more rapid convective heat transfer over the ice alone.
Where's the Beef?
Good meat is hard to come by these days, at least at a price that can feed a hundred or more people for cheap. Thank goodness for Costco. The perfect store for these occasions. It sells a boneless beef chuck rib meat that comes in strips about a foot long and 2 inches in diameter. It's usually got a square cross section which is nice for grilling because it won't roll around, letting you keep track of cooking time per side. The meat is nicely marbled but somewhat tough along the grain with a few sinews. For just $3/lb, it's a bargin. It's great for stew meat and much more tender after a long cooking period. Plus it has great flavour being next to the rib. It is far more moist than a tri-tip or skirt steak at $4/lb, both of which get tough and dry. However, there's a reason why the meat is cheaper. It isn't shaped in anything close to that of a steak being long rather than flat and round. And it can be a bit tough just out of the package without treatment. Also, as far as steaks go, it isn't designed to be served as individual slabs. Instead, it needs to be cut across the grain into slices about 3/4 inch thick and served as small steakettes.
But, there is no doubt this meat can rival the flavour and satisfaction of a ribeye. The key is preparation. Most strips have one side that has a thick, attached membrane that was stuck to the ribs. This needs to be trimmed off and any excess fat removed. This comprises no more than 5% of the weight usually. Then the meat needs time to marinate and break down. There are two schools of marination - one that works and one that doesn't. One school recommends using enzymes to break down muscle fibres and protein, usually with some tropical fruit juice. But as steak aficionados already know, this destroys texture and makes the meat gritty.
The other way is to use some type of chemisty, usually with mild pH differences, and sharp changes in salinity or chemical concentration to drive cellular breakdown or dissication which is more akin to aging. This is exactly the same as brining meats, which makes them retain more moisture during the cooking process, but while in the brine, the tissues soften quickly. Depending on the kind of marinate and the degree of saltiness, temperature and other factors, you may only need to marinate for a few hours. But I like to go easier on the salt and marinate over night and kick in some other flavours. My wife discovered a brand of Korean BBQ sauce that isn't the standard tangy/spicy one used on Kalbee. Instead, this is similar to a Japanese style of steak marinade. Very low viscosity, but very dark. It seems to have some molasses and dark sugars, rice wine, salt, dark soy, and other ingredients. It isn't as salty or sweet or viscous as other sauces. This works very well on chicken and beef, and it especially works well with these rib steaks. A large zip-loc freezer bag with about 5 lbs of meat and about 1 cup of this sauce mixed with 1/2 cup of water seems to do the trick. Since the meat comes mostly defrosted but somewhat still solid in the core, a space saving trick is to use an ice chest and store the meat there overnight. The meat can melt and still stay as cool as the frige, and marinate more quickly.
Coq au Vin
Chicken and white wine just seem to get along extremely well when combined and cooked, releasing aromatic esters. My wife does an oil-n-spice mixture of light olive oil, Montreal Chicken Seasoning and some italian herbs and slathers this over boneless chicken thighs. Generous portions of chicken get shoved into zip-loc bags as well and before throwing them into the cooler, we pour a 1/4 cup of a good white wine, like a $2/bottle Charles Shaw Chardonnay you can get at Trader Joes. It takes less than an hour to process about 60 lbs of chicken this way, and the results are about a dozen bags of ready-to-grill poultry that takes about 15 minutes per batch.
Meanwhile... the BBQ Pits have settled down
After a good 45 minutes, the BBQ Pits settle down - no more big flames and smoke. It's very white and red and very hot. About 20 minutes before the bulk of the people arrive is when I usually take a final pass at cleaning the grill, and then start placing meat over the fire. The fire is not always uniform and there are always hotspots. In addition, the first 30 minutes or so, the flame may be so hot that you really need to watch the meat closely and flip it a lot. In fact, keeping the grill an extra 6 inches higher can allow you to keep up with the flipping. The chicken may have lots of oil residue and it can drip into the fire and cause flare ups. And the fatty parts of the beef can drip as well.
Keeping hands and arms wet and moist is critical early on. Also, having a long metal skewer, like a fireplace poker with a sharp hook on it is better for reaching across to the middle of the grill without sticking your arm over the pit and getting it roasted. Remember to use two sets of tongs and flippers. One for raw, and one for cooked. I make it almost a religious practice to only handle food with the raw food tongs until such time that the exterior is cooked. And then all the handling is using another set. This is the reason for having the fire on one side of the pit. The raw food is placed on my right side, then moves left as I flip it. As I take it off the rack on the left, I switch and use the cooked tongs. For most right handed folks, flipping by rotating the wrist counter-clockwise is easier and hence you want to start out on the right side and flip moving left. Chicken is done in about 15 minutes if it has been kept flat. If the meat is balled up, you will need to check the inside. Sometimes, it can take 25 minutes or more. So it's important to lay the pieces down flat originally on the grill. The steaks take about 20 minutes to cook because they are thicker. Individual chicken pieces can each represent their own serving. But the foot long strips of rib meat are better off being cut across the grain into 3/4 - 1 inch thick slices. This steak is still tender and juicy even medium well, so it is not necessary to have different batches to accomodate those that like their steaks rare or medium rare. Also, for such large parties, it's usually best to error on the side of well-done.
I don't recommend slicing the meat immediately. I prefer to have an aluminum tray or two trays (one for chicken, one for beef) at the colder end of the BBQ to put cooked items into. it's still warm for sure. But just not so hot as to continue cooking. Here, meats can stay warm, but rest for a few minutes. But sometimes, you have no choice if a queue forms waiting for fresh meat off the grill. However, if you did have time, ideally you'd let the strip steaks rest for about 5 minutes and then slice them. This pause gives the meat time to reabsorb some of the juices that were boiling inside and trying to move up through the meat driven by the intense heat.
The hot fire early on is great for cooking fast, and hopefully it satisfies the bulk of customers coming to feed. As the heat reduces, you can lower the grill closer to maintain the cooking capacity, or leave the grill at the same level and reduce your urgency by which you watch the food. Then maybe you can change shifts with an alternate grill-master and schmooze with others.
Sausages, Portabello Patties, Garlic Bread, etc.
Cooking sausages is the same as cooking other meats. The key is to use tongs and not a poker. We don't want to puncture the skin on a sausage and thus allow the juices to escape. Sausages are best left till after the fire is a bit cooler. This is because they tend to have high fat content and can catch fire easily when the grill is extremely hot. It's better to slow roast them. Sausages are ready when the skins get translucent and split or holes start to form and allow juices to escape under pressure. This means the center has reached a pressure above 1 atmosphere, and thus inside the sausage, with the salinity factors, the temperature must exceed the boiling point of water. It's a good practice to leave a sausage that is squirting on the grill for another minute to ensure that the interior is evenly cooked. Afterwards, I also like to slice sausages into bite sized chunks. Those who like it can take more. Those who don't, won't waste as much.
For vegetarian burgers, garlic bread, and other non-meat items, the grill will cause a major reduction in moisture. Garlic bread, because it will toast so quickly over the hot coals, this isn't a real problem. But with any type of vegetarian patty, they can turn into cardboard - literally - they will taste and chew like cardboard. What can work is to pre-fill an aluminum tray with a rich, vegetarian broth and red wine reduction with some type of tomato-base sauce. Off-the-shelf BBQ sauces that are thick and viscous can work here. Taking one part sauce, and one part stock and adding a teaspoon of red wine per liter of total liquid can make a very nice mixture. All this can be placed and mixed inside the aluminum tray, then placed directly on a hot part of the grill. The sauce will simmer after about 10 minutes and begin to reduce. As you finish grilling the Portabello patties, you can then dump them into this sauce and preserve the moisture and add a lot of flavour and also keep them hot. Folks who serve themselves will then have a very nice, moist and rich sauce taste on a vegetarian product. The only problem though is that the non-vegetarians may like this too, and deplete your resources quickly. I came prepared with 2 x 28 packs of vegetarian patties.
Clean up is always a problem. If everyone simply picked up garbage and/or recyclables around them and put stuff in its place, the rest of the things would take care of themselves. But lots of times, folks abandon their messes and others need to pick up after them. I usually travel with all my service ware, supplies, cutting boards, knives, kitchen supplies in large plastic tubs with lids. Dirty stuff all goes into a special tub and gets taken care of at home, and I keep a separate one for small leftover stacks of plates, cups, and other paper products to be used for the next event. Packing and gathering leftover stuff takes less than 15 minutes usually. But I try to allocate 30 minutes for final walk through to clean up the place, and another 30 minutes for sorting garbage from recyclables. It's amazing how many folks will be careless about throwing away a recyclable into a trash recepticle when the recycling bins are just 2 feet away. But allocating time for clean up ensures that next time, the park maintenance folks will welcome you back. Oh, having rolls of paper towels, a pack of food service plastic gloves and a jug of disenfecting wet wipes are pretty much de rigeur for us BBQ warriors!
Total bill for the event came to about $861. The total number of participants could have been about 175 or so. It's hard to say. It sure was a LOT easier hauling stuff back. I was left was just a few bags of chilled meats and supplies, and less than a dozen bottles of water. At $5/person, that's good morale boosting, I think.