BBQ COP said:
I have to tell you I can't wait till this is over.
Aw, cooking for a crowd is fun! I grew up at a camp working with the chef and staff (technically Sous Chefs I guess, but we all were seasonal employees working directly for the chef) cooking for anywhere from 100 to 250 kids, plus a staff of maybe 60 - 75 (whole camp staff, seasonal and FT). What a blast!
My theory with cooking for large numbers of people, especially if the dish(es) store/freeze nicely, is to over estimate, and if you continue to cook for such numbers, scale back accordingly. If you're planning for 100 people, you're thinking allots 3 shells per person. As previously noted, that's a seemingly reasonable quantity for each person, figuring some may go less, and some more.
That said, I think for a 10 hour event, that might be a little light. If everybody decides to eat at once, your 300 stuffed shells may only last as long as it takes them to get through the line. Now, I don't know what other items will be available (I am confident there will be other things, more like salads, side dishes, or finger foods), but that will have a role in how many sheels people eat.
Under the assumption of other items (salads, etc.) I would go with 400 shells. Maybe 350, but since they freeze well, why not 400? Then again, I'm of the mindset to be over prepared then under prepared. Of course, cost has to figure in for the long run, but on an infrequent occasion I'm of the paradigm of more is better.