Bake bread slices on a baking sheet at 425° for 5 minutes. Set aside.
Sauté sliced onion and bell pepper in a large nonstick skillet coated with cooking spray over medium-high heat 5 minutes.
Spread pasta sauce evenly on one side of each bread slice. Top evenly with mozzarella cheese, onion mixture, crumbled patties, and Parmesan cheese.
Bake at 425° for 10 minutes or until thoroughly heated.