If you haven’t already, cook the chicken breasts. You can bake them, pan-sear, or boil them, then shred them into bite-sized pieces using two forks or a stand mixer.
Season the chicken with a pinch of salt and pepper, and set it aside.
2. Cook the Pasta:
Boil the penne pasta according to package instructions, making sure it’s al dente (slightly undercooked, as it will cook further in the casserole). Drain the pasta and set it aside.
3. Assemble the Casserole:
Preheat your oven to 350°F (175°C).
Lightly grease a 9×13-inch casserole dish with olive oil.
In a large bowl, combine the cooked chicken, marinara sauce, garlic powder, onion powder, dried basil, dried oregano, and a pinch of salt and pepper. Stir to coat the chicken evenly in the sauce.
Add the cooked pasta to the bowl with the chicken mixture and toss to combine everything well.
Transfer the chicken and pasta mixture into the prepared casserole dish and spread it out evenly.
Sprinkle the top with grated Parmesan cheese and shredded mozzarella cheese.
4. Bake:
Cover the casserole with aluminum foil and bake in the preheated oven for 20 minutes.
After 20 minutes, remove the foil and bake for an additional 10-15 minutes, or until the cheese on top is melted and bubbly and the casserole is hot throughout.
5. Serve:
Once the casserole is done, remove it from the oven and let it cool for a few minutes before serving.
Garnish with fresh basil for a burst of color and added flavor, if desired.
