Cook pasta according to directions on packet. Drain and toss with one tablespoon of butter, cover and set aside.
In a medium sauce pan over low heat, heat cream and 3 tablespoons of butter, stirring constantly. When cream begins to simmer mix in a small amounts of Parmesan cheese, stirring constantly until all cheese is added and sauce has reduced. It should be thick and easily cover the back of a spoon.
Stir in nutmeg and black pepper. Toss with warm fettuccine to serve.