I’ll agree with the suggestions already posted. I came in to post my own recipe, but it’s so similar to those already posted that it’s not worth the effort. There will always be subtle variations between recipes, but all good alfredos start by heating butter and heavy cream, then fresh grated parmesan is added. I add fresh ground pepper and nutmeg, myself.
Just remember: boiling is not your friend. Hot cream is good…boiling cream is a disaster.