1 onion, diced
3 cans of different beans (I suggest black beans, kidney beans, and pinto beans)
1 can diced tomatoes (or dice your own)
1 package firm tofu, cut into cubes
sliced carrots, celery, and any other random thing you want to throw in
Saute onion and tofu together in a bit of olive oil, then dump in the rest of the ingredients and cook until everything is heated.
Yes, this is easy and fast, but as a college student, I try to think of things that are fast and easy (and cheap!) to make and that will make mass quantities that I can eat all week.