6 servings (3 stuffed shells each)
1. Preheat oven to 350°F. Cook shells according to package directions. Meanwhile, cook sausage, onion, red pepper and garlic in large skillet over MEDIUM-HIGH heat 8-10 minutes or until sausage is thoroughly cooked, stirring frequently; drain.
2. Mix ricotta, 1/2 cup mozzarella cheese, 1/4 cup Parmesan cheese, egg, parsley and oregano in large bowl. Stir in sausage mixture.
3. Drain shells; rinse with cool water. Spread 1 cup sauce onto bottom 13x9-inch baking dish. Add shells; fill each with about 1/4 cup of the sausage mixture. Cover with remaining sauce, and remaining mozzarella and Parmesan cheeses. Cover.
4. Bake 50 minutes or until shells are thoroughly heated and cheese is melted and lightly browned, uncovering after 30 minutes.