Scaling a recipe is done on the yield of the recipe, not the portion.
In order to correctly scale the yield must correspond to the portion.
That’s normally what a ‘serving’ recipe is; the portion and yield are the same (e.g., ea. or serving). Then you can scale the recipe up to the number of portions you want easily.
Prep recipes have a ‘portion’ field, for how you use the prep recipe in another serving recipe.
For any recipe you serve (like 6 oz. of soup from a batch), you should create a serving recipe of ‘ea.’, that uses the portioned amount of the batch. THEN you can scale the portioning recipe up and down as needed, and it will scale the amount of the batch that you need.
There’s a soup example in the SAMP unit (when you start up CostGuard, select SAMP instead of MAIN).
Summary: create a serving recipe for every serving size of the prep recipes you make, THEN scale the serving recipe as needed.