I occassionaly cook for a teenager retreat that has a head count of 40-50. One of the most popular meals is a taco/buritto bar. Here is a sample menu
Taco filling from both ground beef and chicken
Fish Sticks (They are delicious in tacos)
Assorted chopped lettuce
Green onions
Refried Beans
Tomatos
Red and Green peppers
Yellow Rice
Taco shells
Burrito wraps
Sour Cream
Salsa