In a large pot, bring salted water to a boil over high heat. Once boiling, add the rigatoni pasta and cook for 10-12 minutes until al dente. Keep an eye on it, stirring occasionally. When ready, drain the pasta and set it aside in a colander.

Heat 2 tablespoons of olive oil in a large skillet over medium heat. Season the chicken breasts with salt and pepper, then place them in the hot skillet. Sear the chicken for 6-8 minutes on each side, or until golden brown and thoroughly cooked, reaching an internal temperature of 165°F.

In the same skillet, reduce the heat to low and add 4 tablespoons of butter. Once melted, stir in 4 minced garlic cloves and sauté for about 30 seconds, or until fragrant—be careful not to let the garlic burn.

Pour in 1 cup of chicken broth and bring the mixture to a gentle simmer, scraping the bottom of the skillet. After about 2 minutes, stir in 1 cup of grated Parmesan cheese, allowing it to melt and create a creamy sauce.

Once combined, return the chicken and the rigatoni to the skillet, mixing everything until evenly coated.

To finish, sprinkle chopped fresh parsley over the top and add red pepper flakes if desired. Serve immediately.