Bring a large pot of salted water to a rolling boil over high heat. Add pasta and cook until al dente according to package instructions, usually about 8-10 minutes. Reserve ½ cup of pasta water, then drain and set aside.

Pat the chicken dry, season with salt, pepper, and half the Italian seasoning. In a large skillet, heat 1 tablespoon of butter over medium-high heat. Sear chicken for 3-4 minutes on each side until golden brown. Remove from skillet.

In the same skillet, add remaining butter and reduce heat to medium. Add minced garlic and red pepper flakes, cooking for 30-60 seconds until fragrant. Deglaze with chicken broth, scraping browned bits. Add heavy cream and remaining Italian seasoning, simmering 2-3 minutes.

Whisk in Parmesan cheese until the sauce is smooth. Return chicken with juices to the skillet and add drained pasta. Toss gently, adjusting sauce consistency with reserved pasta water. Season to taste with salt and pepper.

Once combined and hot, garnish with freshly chopped parsley. Serve immediately.