Heat 2 tablespoons of butter in a pan. When butter melts, whisk in heavy cream, and pepper/garlic powder (optional) if you would like.
Bring to a light simmer and cook for 2 minutes.
Whisk Parmesan into cream to thicken.
You are ready to add precooked chicken etc. if that is what this is being used for. Fully coat and warm chicken. Serve Immediately. If reheating, you can add a little more heavy cream.