Copyright: Mark Bittman, How to Cook Everything Vegetarian
2 cups well-cooked white, black, or red beans or chickpeas or lentils, or one 14-ounce can, drained
1 medium onion, quartered
1/2 cup rolled oats (preferably not instant)
1 tablespoon chili powder or spice mix or your choice
Salt and freshly ground black pepper
Bean-cooking liquid, stock, or other liquid (wine, cream, milk, water, ketchup, etc.) if necessary
1. Combine the beans, onion, oats, chili powder, salt, pepper, and egg in a food processor and pulse until chunky but not pureed, adding a little liquid if necessary (this is unlikely but not impossible) to produce a moist but not wet mixture. Let the mixture rest for a few minutes if time allows.
2. With wet hands, shape into whatever size patties you want and again let rest for a few minutes if time allows. (You can make the burger mixture or even shape the burgers up to a day or so in advance. Just cover tightly and refrigerate, then bring everything back to room temperature before cooking.) Film the bottom of a large nonstick or well-seasoned cast-iron skillet with oil and turn the heat to medium. A minute later, add the patties. Cook until nicely browned on one side, about 5 minutes; turn carefully and cook on the other side until firm and browned.
Alternate directions (Baking takes longer, but results in a crisper crust, and a drier, more crumbly interior):
Preheat oven to 425. Smear a baking sheet with oil, line it with parchment paper, or use a nonstick sheet. (I used parchment, and the mixture still stuck. I would use Reynolds Release foil the next time.) Bake the burgers until they are deeply colored and release from the pan, about 15 minutes. Then flip and bake for 15 minutes more.
This recipe was discussed here.