Here’s a quick and dirty example:
A 50lbs bag of Wheat Flour costs me $18.02. Working out my food cost, I know that the Wheat Flour contributes $.13 to the cost of each pizza.
So .13/18.02 = .0072… Each pizza is using about .7% of the bag of flour and as such, .7% of the cost, calories, fat, protein, sodium, etc…
So I multiply (# of servings) by (calories per serving) from the Nutrition Facts sheet to find out a 50lbs bag of Wheat Flour contains 78698 calories in total. Now I can use that same percentage to find out 78698 cal x .0072… that the Wheat Flour contributes 567 calories to each pizza. Do that for the other items on the Nutrition Fact sheet, repeat with other ingredients, plug into a spreadsheet and sum total in one column to generate your own Nutrition Facts numbers.
It’s time consuming, but it’d totally doable!