When you need to make bunch of Alfredo sauce for a crowd, here is a recipe that I put together (after looking at lots of recipes) and it actually worked and tasted yummy. I needed this to be really easy to make but also to stay hot for an indefinite time to serve as they came.
In all ingredients in your crock pot"
1c butter
(I originally used 1 1/2 c butter but plan to try cutting that back next time)
1c whipping cream
2c grated Parmesan/Romano cheese blend (I used the very fine drier kind - it might be more creamy with larger/fresher cut cheese but I thought it was fine)
2 - 8 oz pkgs cream cheese
2 c milk
3 cloves of crushed fresh garlic
sprinkling of nutmeg (maybe 1/4 - 1/2 tsp)
Stir as it melts and mixes. Enjoy!