If you like black beans, make the burgers from them. I made them tonight and they are so good. I vary mine from one time to the next by adding this or that and tonight in addition to the spices and a few herbs, I added a leftover baked potato that I mashed and a chunk of chopped and steamed cabbage. I did use an egg to help bind it all together. They were so good I only had a salad of grapes and apples with them.
And that's the other thing, beans are so versatile, there are a lot of things you can do with them aside from just steamed, grilled, or sauteed.