A recipe can be an ingredient
The sauce you make every week is a recipe of its own. So is the spice blend, the dough, the batch of rice. Any recipe you have saved can be added to another recipe as an ingredient, which means you build the sauce once and then spend it across the dishes that use it.
Adding one
In the recipe editor, add an ingredient the way you always do. Your own recipes appear in the results under My Recipes — choose one and give it an amount, exactly like any other ingredient.
How that amount is expressed depends on the child recipe. If it has a Total weight, it comes in by grams, so "180 g of tomato sauce" is a real weight of the finished sauce. Without one, it comes in by servings.
A change to the sauce reaches the lasagna
Edit a recipe and every recipe that contains it recalculates: calories, macros, fiber, sugar, sodium and the full micronutrient breakdown, all the way up the chain. Correct the sauce once and the four dishes built on it are correct too.
Deleting a recipe works the same way. It is removed from the recipes that used it as an ingredient, and each of those is recalculated on the spot, so nothing is left quietly counting a dish that no longer exists.
Diary entries you already logged keep the values they were logged with, as with any recipe edit.
The rules that keep the math finite
Three rules hold the structure together, and the app applies them the moment you pick the ingredient:
- Three levels deep. A rice bowl can contain a sauce that contains a spice blend. One more layer under that is where it stops.
- A recipe cannot contain itself.
- No loops. If the sauce already contains the blend, the blend cannot take the sauce.
Logging the finished dish
Nothing changes at the diary. The parent recipe logs by the serving like any other, with its nutrition already carrying everything its sub-recipes brought.