FWIW, some places use a "Q" factor for costing menu items. What the h3ll is a "Q" factor you ask?
Well, think for a minute, say, for example, dinner service: EVERYBODY gets a breadbasket, butter, salt, pepper, water, glasses, silverware, whatever, the restaurant figure out the "cost" for all those items and comes up with a "number", say oh for example, $0.63/cover. That's the "Q" factor" (and it VARIES with each place and the service they provide!)
Now, add up the protein, starch, veggie, and everything else that goes into the dish AND ADD ON THE "Q" FACTOR, there is your total "food cost" to serve a "cover"!
If you're real lazy and don't care whether you stay in business or not, simply divide by your "planned food cost percentage" (normally somewhere between 20% and 40%, generally around 30%-35%) to get your menu price.
If you really want to stay in business and make money, KNOW what your competition is charging, understand what your customers want, and figure out the gross possible profit from each and every dish on your menu as well as the sales volume (# of orders) based on what the "market will bear".
"Food Cost", IMHO, should NOT dictate "menu price", but should be used as a "management tool" for controlling costs. Just because a majority of successful restaurants have a food cost between 30%-35% does NOT mean that those restaurants set their menu prices by dividing food cost by .3 or .35!
Which would you rather serve, a hamburger plate that costs $3.00 for $10.00 (30% cost of food and a $7.00 gross profit) or a New York Strip dinner for $35.00 that cost you, say, $15.00 (43% cot of food and a $20.00 gross profit)?