baking powder ½ tsp salt

Baking powder is a dry chemical leavening agent composed of an alkaline powder (typically sodium bicarbonate, commonly known as baking soda), one or more acidic ingredients (most commonly cream of tartar or sodium aluminum sulfate), and a moisture-absorbing agent such as cornstarch or potato starch. This combination enables the release of carbon dioxide gas when the powder is moistened and/or heated, causing dough and batter to rise during baking. Most commercial baking powders are "double-acting," meaning they release gas both when wet and when heated, providing lift at two critical stages of the baking process.

The ratio of base to acid is carefully balanced—typically around 4 parts sodium bicarbonate to 1 part acid—to neutralize all the base and leave no bitter taste or soapy flavor in the finished product. Single-acting baking powders, though less common today, release gas only when moistened and must be used immediately. The starch component prevents premature reaction and caking during storage.

Baking powder is indispensable in quick breads, cakes, cookies, biscuits, pancakes, and muffins—any baked good requiring immediate rise without fermentation or leavening agents like yeast. It is added to dry ingredients before wet ingredients are combined, allowing the chemical reaction to begin upon contact with moisture. In some recipes, baking powder works alongside eggs or other ingredients that contribute additional leavening. The amount used is critical: too little produces dense, flat baked goods; too much creates an unpleasant metallic or soapy taste and can cause rapid over-rising followed by collapse. Baking powder is used across numerous cuisines wherever quick breads and cakes are prepared.