American Baker in Germany

 It can be confusing. Baking powder. Baking soda. They sound similar. Seem to be used in similar amounts in baking recipes and seem to be used for the same general reason. They even look kind of similar. So, what's the difference?  Let's start with baking soda. Baking soda is a single chemical. It's called sodium bicarbonate, which is a base. If you don't remember what that means, it's basically the opposite of an acid, which means it will react with acids. Baking soda is called for in recipes when there is also an acid in the recipe somewhere. Examples of acids are: lemon juice, citric acid, cream of tartar, vinegar, buttermilk, molasses or even brown sugar. Baking soda makes the batter or dough swell up by reacting to the acid in the recipe.  Now let's look at baking powder. Baking powder typically contains three ingredients: a base such as sodium bicarbonate or sodium biphosphate, an acid such as cream of tartar, and corn starch. Because baking...