You can edit the ingredients section of a recipe as described in this article. Ingredients can be added from multiple food databases, and their portion sizes and nutrients will be computed automatically.
Step 1: Open the recipe you want to edit as shown in this tutorial.
Step 2: Click on the Ingredients tab.
Step 3: You can now use the nutrition search bar to add ingredients to the recipe. To learn how to use the nutrition search bar, please check this tutorial.
Step 4: As you add ingredients to the recipe, you can edit their name and portion sizes. The ingredients will be added to the ingredient editor spreadsheet. To learn how to operate the spreadsheet, please have a look at this tutorial
That's it, changes are saved automatically as you add/edit ingredients. To learn how to edit the other components of your recipe, please have a look here.