Buttermilk is a very popular ingredient in cakes and quick breads whenever the creaming method is used. Its inherent acidity allows us to use baking soda in addition to or instead of baking powder as a leavening agent. If it is not combined with an acidic ingredient, baking soda alone becomes carbon dioxide gas and sodium carbonate when it is heated. The carbon dioxide gas is what we want to produce the air bubbles and leavening effect, but the sodium carbonate leaves behind a disagreeable,