Aluminium-free baking powder

Commercial baking powders contain unhealthy aluminium compounds as well as other ingredients detrimental to health.  This takes seconds to make, performs well and has no bitter after taste.  It is courtesy of Rebecca Wood, in her excellent The New Whole Foods Encyclopedia.

Makes 1 1/4 cups

1/4 cup baking soda, 1/2 cup cream of tartar, 1/2 cup arrowroot powder

Mix all the ingredients together and store in an airtight container.  Substitute equal parts for commercial baking powder in any recipe.  It keeps for one year.