The sauce of Chicken Alfredo is made of butter, heavy cream, Parmesan cheese, garlic, and seasonings. Butter provides richness, while heavy cream adds creaminess. Parmesan cheese contributes a salty and nutty flavor. Garlic brings a savory element, and seasonings like salt and black pepper enhance the taste. These ingredients are combined and simmered to create a creamy and flavorful sauce that coats the chicken and pasta, resulting in a deliciously indulgent dish.