In a large skillet, cook the beef, pepper and onion over medium heat until meat is no longer pink; drain. Add the tomato sauce, tomato paste, water, garlic, sugar, Italian seasoning and salt. Bring to a boil. Reduce heat; simmer, uncovered, for 10 minutes or until heated through.
Cut 1/4 in. off the top of each roll; set aside. Carefully hollow out bottom of roll, leaving a 1/4-in. shell (discard removed bread or save for another use). Fill each roll with 1/2 cup meat mixture. Sprinkle with cheeses. Replace bread tops.
Place desired amount of sandwiches on a baking sheet. Bake at 350° for 10-15 minutes or until heated through. Individually wrap remaining sandwiches tightly in foil; freeze for up to 3 months.
To use frozen sandwiches: Thaw in the refrigerator overnight. Remove from the refrigerator 30 minutes before baking. Place foil-wrapped sandwiches on baking sheet. Bake at 350° for 30-35 minutes or until heated through.