Cook shells following package directions. Drain; let cool.
Heat oven to 350°F. Combine ricotta cheese, Parmesan cheese, 1/2 cup shredded mozzarella, broccoli, basil, salt and pepper in a medium-size bowl.
Spoon 1/2 cup red sauce evenly over bottom of 12 x 8-inch glass baking dish. Spoon about 1 heaping tablespoon cheese-broccoli filling into each shell. Arrange shells in single layer in baking dish. Spoon remaining sauce over stuffed shells. Sprinkle with remaining mozzarella. Cover dish.
Bake in 350°F oven 30 minutes. Uncover; bake 30 minutes. Serve with salad and garlic bread.