In a large skillet, cook beef and onion over medium heat until meat is no longer pink; drain. Stir in the bell pepper and garlic; cook for 2 minutes. Add the beans, tomatoes, tomato sauce, chili powder, cumin, salt and pepper. Simmer for 20 minutes.
In a greased 13x9-in. baking dish layer half of the beef mixture and 1 cup of cheese.
Repeat layers ending with cheese.
Bake uncovered at 350° for 25 minutes or until bubbly.