Creating High Protein Casserole Chicken Parmesan is straightforward with the following steps:

1. Preheat your oven to 350°F (175°C).
2. In a large skillet, heat the olive oil over medium heat.
3. Add the diced chicken to the skillet, seasoning with garlic powder, onion powder, Italian seasoning, salt, and pepper.
4. Cook the chicken until it is no longer pink in the center, about 6-8 minutes.
5. In a large mixing bowl, combine the cooked chicken, marinara sauce, and cooked pasta. Stir well to combine.
6. Transfer the mixture to a greased casserole dish.
7. Top with shredded mozzarella cheese and grated Parmesan cheese.
8. Bake in the preheated oven for 25-30 minutes or until the cheese is bubbly and golden brown.
9. Remove from the oven and let it cool for a few minutes.
10. Garnish with fresh basil leaves before serving.

These steps will guide you in creating this incredible casserole effortlessly.