Follow these simple steps to create your Chicken Parmesan Casserole:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Prepare the Chicken: In a large bowl, combine the cooked chicken, marinara sauce, dried basil, dried oregano, garlic powder, salt, and pepper. Mix until well combined.
3. Cook the Pasta: Cook the pasta according to package instructions until al dente. Drain and set aside.
4. Combine Ingredients: In the same bowl with the chicken mixture, add the cooked pasta and half of the mozzarella cheese. Stir until evenly mixed.
5. Transfer to Baking Dish: Pour the mixture into a greased 9×13-inch baking dish, spreading it evenly.
6. Add Toppings: Sprinkle the remaining mozzarella cheese and grated Parmesan cheese over the top.
7. Bake: Place the baking dish in the preheated oven and bake for 30-35 minutes, or until the cheese is bubbly and golden brown.
8. Cool Before Serving: Once baked, remove the casserole from the oven and allow it to cool for a few minutes.
9. Garnish: Optionally, garnish with fresh basil before serving.

These straightforward steps will guide you in making this incredible casserole effortlessly.