Place beans, oats, vegetables, salt, and spices in a food processor and pulse until combined but not pureed. Remove from food processor and place in a bowl. Mix in 2 to 3 tablespoons of reserved bean cooking liquid and mix. Refrigerate 1 hour.
Heat olive oil in a heavy skillet. Shape bean mixture into 5 1-inch thick burgers. When oil is hot, place burgers in skillet over medium heat. Cook 5 to 7 minutes or until browned on the bottom. Carefully flip burgers over and cook another 5 to 7 minutes or until browned and crispy.
Serve on a bed of lettuce with tomato slices and mustard or on a bun with your favorite toppings.
NOTE: If a food processor is not available, place the ingredients in a bowl and mash with a potato masher.
Per serving - 235 calories, 15 g fat (56% calories from fat), 6 g protein, 22 g carbohydrate, 6 g fiber, 0 mg cholesterol, 270 mg sodium