[header] How to make pasta with alfredo sauce from a jar [title] Decide how much pasta you need. [step] The average serving size is 2 ounces of pasta per person. That's about half a handful of dried fettuccine noodles, or half a cup of dried macaroni. 
Decide how much pasta you want to cook and measure it out from the box. [substeps] If you find it easier to cook the whole box, that's fine, too.