HOMEMADE BAKING POWDER 

Sift together two parts cream of tartar to one part baking soda for homemade baking powder that doesn’t leave behind a metallic trace.

MAKE YOUR OWN CAKE FLOUR

Start with 1 cup all-purpose flour and remove 2 tablespoons.  Substitute the 2 tablespoons of flour you removed with 2 tablespoons of cornstarch.  Whisk together to mix well or sift 4 or 5 times. Use this as a substitute for cake flour.  You can always make more and store in an air-tight container for future use in recipes.