In a large saucepan with a tight-fitting lid, cook beef, onion and garlic over medium heat for 5 minutes or until beef is browned on the outside and no longer pink in the center, stirring occasionally to turn and break up the beef.

Pour into a colander and rinse under hot water to remove excess fat; drain well.

Return beef mixture to saucepan. Raise heat to high and stir in broth, macaroni and salt; bring to a boil then reduce heat, cover and simmer for 5 minutes.

Stir in undrained tomatoes, bell pepper, chili powder, cumin, oregano and cayenne pepper. Cover and cook for 10 minutes or until macaroni and bell pepper are tender.

To serve, ladle into bowls; sprinkle with the green onions and cheese.