You bought Baking Powder at the grocery store, and you may notice that the can says it is "double-acting". Does this mean you need to use only half as much as a recipe calls for?
Nearly all Baking Powder available today is double-acting Baking Powder. This means it contains two different types of acids that react at different times. The first acid will react by creating gases when mixed with the liquid in the recipe. The second type will react by creating gases when the batter is exposed to oven heat. Our recipes are tested with double-acting Baking Powder, so use exactly the amount listed in the recipe.