Q. The cooking part comes fairly easy to me but it is the quantities I have trouble with. How much roast beef, mashed potatoes & gravy would you need to serve 55 people.
A.
With boneless cuts of meat, figure on a half-pound or slightly more per person. Plan on three-quarters cup of mashed potatoes per person and three ounces of gravy. So that would be 30 pounds of meat, about 3 gallons of mashed potatoes, and a little more than 5 quarts of gravy.