In a skillet over medium heat, add the ground beef and cook until browned, about 5-7 minutes.

Drain excess fat if necessary.

Add the diced onion, bell pepper, and garlic to the skillet. Cook until vegetables are softened, about 5 minutes.

Stir in the diced tomatoes, black beans, chili powder, cumin, salt, and pepper. Simmer for 10 minutes.

Serve hot, topped with shredded cheese, sour cream, and cilantro if desired.