Heat oven to 350°F. Spray 3-quart casserole with cooking spray. Cook and drain pasta as directed on package using minimum cook time. Return to saucepan.
Meanwhile, in 12-inch skillet, cook and stir sausage, onion, bell pepper and garlic over medium-high heat about 7 minutes or until sausage is no longer pink and onion is softened. Stir in pizza sauce, bacon and pepperoni. Pour mixture over cooked pasta; stir. Spoon half of pasta mixture (about 4 cups) into casserole. Sprinkle with 1 cup of the cheese. Spoon remaining pasta mixture on top.
Bake 30 minutes; top with remaining 1 cup of cheese. Bake 5 to 10 minutes longer or until hot and cheese is melted and bubbly.