Season the chicken. Pat the chicken dry and season with salt, pepper, and a pinch of Italian seasoning if you like. This helps the chicken brown and boosts flavor.

Sear the chicken. Heat olive oil in a large pot or deep skillet over medium-high heat. Add the chicken in a single layer and cook until lightly browned and mostly cooked through, 4–6 minutes. Transfer to a plate. Do not wipe the pot; those browned bits are flavor.

Sauté the aromatics. Lower the heat to medium. Add butter to the pot. Once melted, add the garlic and cook for 30–60 seconds until fragrant. Avoid browning the garlic.

Deglaze and add liquid. Pour in a splash of chicken broth and scrape the bottom to release browned bits. Add the rest of the broth and the heavy cream. Stir and bring to a gentle simmer.

Add the pasta. Stir in the dry pasta and a pinch of salt. Keep the heat at a steady simmer (not a rolling boil) and cook uncovered, stirring frequently to prevent sticking, until the pasta is al dente, about 10–12 minutes. The liquid will reduce and thicken.

Return the chicken. Add the seared chicken and any juices back to the pot during the last 3–4 minutes of pasta cooking. This finishes the chicken and lets flavors meld.

Add the cheese. Turn the heat to low. Stir in the Parmesan a handful at a time until melted and the sauce turns silky. If the sauce feels too thick, add a splash of broth or warm water. If it’s too thin, simmer 1–2 more minutes.

Adjust seasoning. Taste and add salt, pepper, and red pepper flakes if desired. A small squeeze of lemon brightens the richness without making it tangy.

Finish and serve. Remove from heat. Let it sit 2 minutes to set. Garnish with chopped parsley and extra Parmesan. Serve hot.