Whenever I'm in the need of easy comfort food this is it. Whenever I'm running out of money this is it. Whenever there's lots of people to be fed, this is it. Here's what you need:
beans (dried are cheaper, but take time)
tomatoes in some form (chopped, crushed, pulp)
spices (like basil, pepper, paprika)
water
Optional ingredients like cream cheese, onions and bread croutons