Step 1: Fill a large pot with salted water and bring it to a rolling boil. Add the rigatoni and cook until al dente. Before draining, scoop out ½ cup of the pasta water and set it aside. Drain the pasta and set it aside as well.

Step 2: Pat the chicken dry with paper towels. This helps it brown instead of steaming. Season it generously with Italian seasoning, salt, and pepper. Heat the olive oil in a large skillet over medium-high heat. Add the chicken and cook for 6 to 7 minutes, stirring occasionally, until the pieces are golden and fully cooked. Transfer the chicken to a plate and keep warm.

Step 3: Lower the heat to medium. Add the butter to the same skillet and let it melt. Stir in the minced garlic and cook for about a minute, just until fragrant. Sprinkle the flour over the butter and whisk constantly for about one minute to form a roux.

Step 4: Slowly pour in the heavy cream while whisking to keep the sauce smooth. Let it bubble gently for 3 to 4 minutes, thickening slightly. Stir in the Parmesan, mozzarella, cheddar, and garlic powder if using. Keep whisking until the cheeses melt completely and the sauce is silky. If it gets too thick, add a splash of the reserved pasta water until it’s just right.

Step 5: Return the rigatoni and chicken to the skillet. Toss well so every piece of pasta is coated in sauce and the chicken is evenly distributed. Let it simmer together for one more minute so the flavors meld.

Step 6: Sprinkle fresh parsley on top before serving. Bring it straight to the table while it’s hot and gooey.