1. Cook pasta according to package directions. Drain; set aside.
2. In a large skillet cook the sausage, onion, and garlic until sausage is brown; remove from skillet. Drain.
3. In a large bowl stir together pasta sauce, 3/4 cup of the mozzarella cheese, and the pepper. Add the cooked pasta and the drained sausage mixture. Stir gently to combine. Spoon the mixture into a 2-quart casserole.*