2 sticks unsalted butter
1 - 1 1/2 c heavy cream
1/4 - 1/2 cup freshly grated Parmesan cheese
2 cloves garlic
fresh flat leaf parsley
Melt butter in saucepan, add garlic and let cook. Whisk in cream, allow liquid to get hot, and gradually whisk in cheese over low heat. Let sit for a few minutes to allow to thicken.
Serve over fresh fettuccine, which holds the sauce's thickness best.