Instructions:

Preheat your oven to 375°F (190°C). In a large pot, bring salted water to a boil and cook the rigatoni pasta until it's almost al dente, following package instructions. Drain and set aside.

In a large skillet over medium heat, sauté the diced onion, chopped carrot, and chopped celery until they're softened, about 5 minutes.

Add the minced garlic and sauté for an additional minute until fragrant.

Add the ground chicken to the skillet and season with salt, pepper, and Italian seasoning. Cook until the chicken is browned and cooked through, breaking it up with a spoon as it cooks.

If desired, stir in heavy cream for a creamier sauce.

Pour in the marinara sauce and stir to combine. Allow the mixture to simmer for about 5 minutes to meld the flavors.

In a large mixing bowl, combine the cooked rigatoni with the chicken and sauce mixture, ensuring the pasta is evenly coated.

Transfer the mixture to a greased baking dish.

Top the rigatoni with shredded mozzarella and grated Parmesan cheese. Bake in the preheated oven for 20-25 minutes or until the cheese is melted and bubbly.

For a crispy top, broil for an additional 2-3 minutes, keeping a close eye to prevent burning.

Remove from the oven and let it cool for a few minutes before serving.

Garnish with fresh basil or red pepper flakes if desired.