Creating this delicious Pizza Casserole is straightforward if you follow these steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Cook the Meat: In a large skillet over medium heat, add the ground beef and cook until browned. Drain excess fat.
3. Sauté Vegetables: Add the diced onion and minced garlic to the skillet. Sauté until the onion is translucent.
4. Add Sauce and Seasoning: Stir in the pizza sauce, Italian seasoning, salt, and black pepper. Allow it to simmer for a few minutes.
5. Combine Pasta: In a large mixing bowl, combine the cooked pasta with the meat sauce mixture. Stir until well mixed.
6. Layer the Casserole: In a greased 9×13-inch baking dish, spread half of the pasta mixture. Top with half of the mozzarella cheese and half of the pepperoni (if using). Repeat the layers with the remaining pasta, cheese, and pepperoni.
7. Add Parmesan: Sprinkle the grated Parmesan cheese over the top layer.
8. Bake: Cover the dish with aluminum foil and bake in the preheated oven for 20 minutes. Remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and golden.
9. Cool and Serve: Once baked, remove the casserole from the oven and let it cool for a few minutes before serving.

This step-by-step guide will lead you through the process of creating an amazing Pizza Casserole that’s sure to impress.