In a large skillet over medium heat, add the ground beef. Cook until browned, breaking it apart with a spatula, about 5-7 minutes.

Drain excess fat if necessary.

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

Stir in the diced tomatoes, black beans, chili powder, cumin, salt, and black pepper. Bring to a simmer and cook for an additional 10 minutes.

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