Cook the pasta in salted water till al dente. Drain and set aside, saving 1/2 cup of pasta water.
Season the chicken with salt, pepper, and Italian seasoning and cook on pan in olive oil until browned about 5-7 minutes per side with an internal temperature of 165 degrees. When you flip it, add the butter to the pan for extra flavor.
Transfer chicken to cutting board, let rest for a couple minutes and then slice into 1/2 inch thick strips. Cover with foil until ready to serve.
For the sauce, melt the butter in a saucepan over medium heat. Sauté the garlic for a minute, add the flour and sauté for another minute or two, stirring well. Add the cream, milk, salt, pepper, garlic powder, and parsley and bring to a simmer, whisking constantly. Stir in the Parmesan cheese and heat just till melted and sauce is smooth. If too thick add some of the reserved pasta water or more milk.
Mix the sauce into the noodles and plate. Add the chicken strips on top. Garnish with parsley, more Parmesan, and black pepper if desired.