This is the ultimate vegetarian burger. Hearty black beans are loaded with flavor to deliver a burger that will satisfy the whole family.
In the bowl of a food processor with a blade attachment, grind 1 hamburger bun until finely ground into breadcrumbs. Pour into a small bowl and set aside.
In the same food processor bowl, add in the garlic cloves and cilantro. Pulse a few times until minced. Add in the beans and purée until smooth. Transfer to a mixing bowl and stir in the chili powder, lime zest, and breadcrumbs. Season, to taste, with salt and freshly ground pepper. Add in the egg and mix until incorporated. Divide mixture into 4 equal pieces and shape into round patties.
In a grill pan, heat oil over medium-high heat. Grill the patties on one side, for about 3-4 minutes until brown. Flip over and add cheese. Cook for about another 3-4 minutes, until cheese has melted.
Serve patties on the hamburger buns with you favorite burger toppings.