Preheat oven to 400 degrees F. Cook and drain pasta as directed on package. Use the minimum cooking time (el dente as the pasta will continue to cook when you bake it). Once done cooking drain and set aside.

Heat olive oil in a large skillet over medium high heat. Add Italian sausage and onion. Cook and breaking up the sausage, until browned, about 3-5 minutes. Drain off any excess fat. Take half of your pepperoni and cut them into 1/4th. Stir that pepperoni into your beef mixture.

Stir in pizza sauce, oregano, basil and garlic powder.

Spray 13x9-inch (3-quart) glass baking dish with cooking spray. Place cooked pasta and sausage mixture into baking dish. Gently stir to combine.

Sprinkle top with mozzarella and parmesan cheese. Place the remaining whole pepperoni slices on top.

Bake uncovered for about 6-10 minutes until cheese is melted and golden brown. Serve immediately.