Beans are an excellent addition to any dish and they have the added benefits of being cheap, delicious, and very good for you. Chili is one of my favorite incarnations, as well as black beans in chilis with adobo sauce. You can usually find a can of these chilis in adobo in an "ethnic food" section or "mexican" section for about 2-3 dollars. They are extremely spicy though so if you don't like spicy it is best to avoid them.