Adding negative food

Markm

i ordered a fast food item without bun. All that’s in the database is the standard item WITH bun so i had to add it. I wanted to make a custom food with the 40g of carbs then add that to the diary with quantity MINUS 1 to subtract the carbs I didn’t eat. Why can’t I do that? Or make the custom food with MINUS 40g carbs?

joshjosh100

I believe the intent is to add the FF item without the bun instead of just adding a bun and adding -1 bun to diary.