In a large saucepan, cook the beef, onions, green pepper and garlic over medium heat until meat is no longer pink; drain. Stir in ketchup and chili powder. Simmer, uncovered, for 2-1/2 hours or until thick and bubbly, stirring occasionally.
Serve over hot dogs in buns; sprinkle with cheese.
Editor's Note: To easily turn hot dogs on a grill, thread them end to end onto metal skewers.