Homemade Baking Powder Recipe

Royal Baking Powder was a single-acting product made years ago. Here's a recipe for single-acting baking powder you could use in old recipes calling for Royal brand.

2 tablespoons cream of tartar
1 tablespoon baking soda
1 tablespoon cornstarch

Combine ingredients and store tightly covered. For double-acting baking powder, use 1/4 teaspoon of baking soda and 1/2 teaspoon of cream of tartar for each teaspoon needed.