Good news: you have choices. Cream of tartar is an oft-overlooked pantry staple. The white powder helps to stabilize whipped ...

as you may have something in your pantry that will work as a substitute (especially if you bake a fair amount): cream of ...

Angel food cake, often served with fresh berries and whipped cream, gets its fluffy consistency from egg whites beaten with ...

This should be your go-to substitute for baking powder. The baking powder you buy from the store is cream of tartar plus baking soda, so combining them at home will get you the exact same result.