I tweaked this recipe from

1 16 oz can black beans
2 green and 1 red pepper from my mom's garden (1/2 cup chopped total)
1/2 medium onion
4 cloves garlic
1/3 cup salsa
1 sleeve fat free saltines
Drain the black beans, getting as much liquid out as possible. Chop the peppers, garlic and onion, add to drained black beans. Mash all together to form paste (it will be liquidy still). Add crushed crackers a little bit at a time -- you're looking for a thick paste that can easily be formed into burgers (we used an entire sleeve of crackers). Add salsa to taste (mine came out only slightly spicy, my mommy doesn't like spicy foods)
Form burgers in your hands, fry in small amount of olive oil. A brown crust should form on each side.
I had lettuce on mine, the girls had ketchup on theirs, my mom ate hers with lettuce and tomato, and Debbie R. (the girl's mom/family friend/cook) ate hers without a bun-- honestly I think they didn't need any extra flavor whatsoever
My only problem with them was that when you bit down into the burger, they were very easy to bite through- it didn't have the texture of meat. Debbie R. said that if you fry the mixture first before forming into patties that it will have a more dense, meatier texture. It wasn't BAD this way, I was just slightly surprised.