Mash a can of drained and rinsed black beans with a fork until chunky. Stir in chopped onion, garlic, breadcrumbs, an egg, and spices like cumin and chili powder. Form the mixture into patties and cook on a grill or in a skillet over medium-high heat until cooked through. Toast buns and spread with mayonnaise and mustard. Top each patty with lettuce, tomato, and avocado slices, and serve on the toasted buns.\n\n
How do you make a veggie burger?