Homemade Baking Powder

Back in the "good ol' days" before packaged baked goods and breads, people made their own baking powder. The individual ingredient are shelf stable in air tight containers and will last for a very long time. Once mixed however, they react quickly, so just make enough for your current recipe and add at the end. 1 part baking soda 1 or 2 parts cream of tartar You can use 1 part cream of tartar if you have another acid in the recipe, like sour milk or lemon juice, sour cream cookies come to mind, and 2 parts cream of tartar if you don't....like chocolate chip cookies. I use the 2 to 1 ratio when substituting for baking powder in most recipes. Making your own baking powder will save money and help to avoid harmful additives like aluminum and cornstarch (most likely GMO).