I love serving these delicious subs to enjoy while watching football, or on a Sunday when you want to relax. They are quick and easy to prepare and everyone loves them. I like making my own meatballs, but if you don't have time pick up a package of frozen, cooked meatballs in your grocer's freezer. Note: I like serving these subs with potato chips or potato salad.
Cook onion, pepper and water, covered, in a large saucepan over medium heat just until tender; drain. Stir in pizza sauce and meatballs; cook until hot and bubbly. Fill each roll with 6 meatballs; top with sauce mixture. Sprinkle with cheese and add roll tops.
Place sandwiches in a lightly greased 13"x9" baking pan. Bake at 400 degrees for 10 to 15 minutes or until bread is crusty and cheese melts.