Season both sides of the chicken with Italian seasoning and a pinch of salt.
Heat oil in a skillet over medium heat and cook chicken for 7–8 minutes per side until fully cooked. Remove and set aside.
Reduce heat to medium-low. Add butter and garlic, cooking for about 2 minutes.
Pour in heavy cream, whisking to combine, and let it gently simmer.
Meanwhile, cook fettuccine in boiling water until tender. Reserve ½ cup pasta water before draining.
Add Parmesan to the sauce and stir until melted and smooth. Let the sauce thicken slightly.
Season with salt and pepper.
Add pasta to the sauce and toss. Add reserved pasta water if needed.
Slice chicken and serve over the creamy Chicken Alfredo pasta. Garnish with parsley.