Prepare the black beans: Ensure the black beans are thoroughly rinsed and drained. Pat them dry with paper towels to remove excess moisture, which is crucial for patty formation.

Mash the beans: In a large mixing bowl, add about two-thirds of the drained black beans. Use a potato masher or the back of a fork to mash them until mostly broken down but still with some texture. Add the remaining whole beans and gently mash a few more times.

Combine ingredients: Add the breadcrumbs, chopped red onion, chopped bell pepper, minced garlic, beaten egg (or flax egg), cumin, smoked paprika, chili powder, salt, and pepper to the bowl with the mashed beans. Mix everything together thoroughly until well combined. The mixture should hold together when squeezed.

Form the patties: Divide the mixture into 4 equal portions. Shape each portion into a patty, about 3/4 inch thick. If the mixture is too wet, add a tablespoon more breadcrumbs. If too dry, add a teaspoon of water or olive oil.

Cook the burgers: Heat the olive oil in a large skillet or on a griddle over medium heat. Carefully place the patties in the hot skillet. Cook for 4-6 minutes per side, until golden brown and heated through. Avoid overcrowding the pan; cook in batches if necessary.

Assemble your burgers: Toast your burger buns if desired. Place a cooked black bean patty on the bottom half of each bun and top with your favorite condiments and toppings. Serve immediately.