Begin by bringing a large pot of salted water to a rolling boil over high heat. Add your choice of pasta and cook until al dente, about 8-10 minutes. Reserve 1 cup of the starchy pasta water for later and drain the rest.

In a large skillet, melt 2 tablespoons of butter over medium-high heat. Add diced chicken breast, seasoning generously with salt and pepper. Sauté the chicken for 6-8 minutes until cooked through and golden brown. Remove chicken and set aside.

In the same skillet, reduce the heat to medium and add the remaining butter. Toss in minced garlic and diced onion, sauté for 3-4 minutes until onion is translucent and fragrant.

Pour in the heavy cream and chicken broth, stirring well. Add Italian seasoning and red pepper flakes, bringing the mixture to a gentle simmer. Thicken the sauce for about 5 minutes, adjusting with reserved pasta water as needed.

Return the sautéed chicken and drained pasta to the skillet, tossing until well coated. Heat through for an additional 2 minutes to meld flavors.

Serve warm, sprinkling with grated Parmesan cheese and garnishing with fresh parsley. Enjoy!