Drain and rinse black beans.

Mash black beans with a potato masher until chunky.

Finely dice bell pepper and green onions.

Finely dice carrot.

Mince garlic.

Juice half a lime.

In a large bowl, combine mashed black beans, diced bell pepper, green onions, lime juice, diced carrot, cumin, cayenne pepper, salt, pepper, minced garlic, egg, and bread crumbs.

Mix the ingredients with your hands until the mixture is firm and sticky.

Add more bread crumbs if the mixture separates too much.

Separate the mixture into 3 black bean burger patties.

Grill the patties over medium heat on a piece of aluminum foil for about 5-8 minutes on each side, or until heated through and slightly browned.

Toast the buns.

Slice the avocado.

Serve the black bean burgers on toasted buns with sliced avocado and hummus.