1st Attempt to cook for crowd. Alfredo (Side dish) Main ingredients in recipe I want to use: 1/2 C Butter 2 C Cream 1/4 C Parmesan Cheese 12 oz. Fettuccine Recipe says will serve 3 as an entree. (I am serving as a side dish) Please help me determine exact amounts of each ingredient for 250 people. I made one batch and it seems like a LOT more than 3. Also, because of prep and serving I thought I might use Penne pasta rather than Fettuccine. Any help appreciated. 1st timer, don't want to flop.