"I believe that if life gives you lemons, you should make lemonade and try to find somebody whose life has given them vodka, and have a party."Ron White
I get this one a lot: "I made the mistake of having the preacher over on July 4 and he loved my pulled pork. Now he wants to cook for the church social next Sunday. I've never cooked for 100 people before. How much should I cook?" The answer depends on a lot of variables.
Gender and age. How many men, women, and children, and what age group? A crowd of young men will eat more than a crowd of old women. Teenagers can really pack it away.
What is the occasion? A church social? A graduation party? A football tailgater? Bridal shower? Bachelor party? Graduation party? Tailgater? Office party? Business meeting? Church social? You need more for a bachelor party than a bridal shower.
How long will the event go on? Is it sit down or buffet? You need more for buffet because people tend to overserve themselves.
When is it? What time of day are you serving? At lunch they may eat less than at supper time. Week night or weekend?
What else is being served? Are the appetizers just chips, or are they more filling, like cheeses? That means you'll need less meat for the entree. What about side dishes? Beans and slaw, or just a tossed salad?
Will there be alcohol? If there is booze, people will eat more to keep from getting drunk. Other intoxicants can cause the munchies...
Plan for leftovers. In any case cook more than you think is needed because the worst thing you can do is run out and have people running to White Castle. If there are leftovers, you can share them with your guests, or save them for yourself.
Ask about dietary restrictions. If there is someone who cannot eat meat or whatever you are cooking, have someone else handle prep for these people. You stay on task.
Rules of thumb
Whatever you do, don't run out. It's better to have leftovers for yourself or to give to your guests. I plan on 1/2 pound of raw weight of meat per person unless the crowd is all big hungry men with lots of beer and football. Then I may go up to 1 full pound per person. Remember to allow for bones. This allows for shrinkage and leftovers. For drinks, I plan on two drinks per person, per hour.
Appetizers. 4 bites per hour.
Poultry, meat, or fish. 8 ounces by weight when you have one main dish, 6 ounces when you offer two or more main courses.
Rice or grains. 3 ounces as a side dish, 6 ounces in a main dish such as risotto.
Potatoes. 5 ounces.
Vegetables. 4 ounces.
Beans. 2 ounces.
Pasta. 4 ounces for a side dish or a first course, 8 ounces for a main dish.
Salad. 5 ounces undressed weight.
Cake, tart, or pastry. 1 slice.
Pudding or mousse. 4 ounces.
Ice cream. 5 ounces.
Plan thoroughly. Walk through the steps in your head thinking of every detail. Here are some tips from Martha Stewart.
There is little problem in scaling up. Just multiplying quantities will work fine.
Do some steps ahead. Prep the meat the day before. Make the rub and sauce well in advance.
If you're going to load up the cooker with meat for a crowd, you want to read my article When You're Cooking More Than One Hunk of Meat.
If you want to cook on Saturday and serve on Sunday, read my article Cook Today, Serve Tomorrow, The Wozniak Way.
If you need to hold warm meat, do it safely. Read my article on food safety. If you are serving buffet style, foods must be kept at safe temps! Use a good digital thermometer and a faux cambro. If somebody gets sick they can sue you and even if they don't win, they can cost you a lot of money!
KISS: Keep it simple, stupid. If you serve three meats, some people will take a taste of all three.