This totally does the job that store bought corn filled baking powder will do. I have found cream of tartar in the bulk spice bin at a local health food store here in Texas but you won’t have any problem finding it cheap in bulk online. You will use ALL of it in this recipe but it lasts a really long time and you’ll be using it a lot when baking goodies so it’s all good!
1/3 C baking soda
2/3 C creme of tartar
2/3 C tapioca starch
1. Whisk together in a small bowl and funnel into a glass jar with a tight lid.
Tip: For smaller quantities use a 1:2:2 ratio of baking soda, cream of tartar and tapioca starch respectively. For example, 1/2 ts of backing soda mixed with 1 ts each of the other two parts will work in a pinch.