In a large mixing bowl, combine the shredded chicken, marinara sauce, cooked pasta, mozzarella cheese, Parmesan cheese, Italian seasoning, garlic powder, salt, and pepper. Mix until well combined.
Transfer the chicken mixture into a greased 9×13 inch baking dish, spreading it evenly.
Sprinkle the breadcrumbs over the top of the casserole for a crunchy topping.
Bake in the preheated oven for 25-30 minutes, or until the cheese is bubbly and the breadcrumbs are golden brown.
Remove from the oven and let it cool for a few minutes. Garnish with fresh parsley before serving.
Notes
Feel free to use leftover rotisserie chicken to save time.
This dish can be made ahead of time and stored in the refrigerator before baking.
To make it spicier, add red pepper flakes to the mixture.