Baking powder has many uses, both in and out of the kitchen. Use baking powder to clean countertops, stainless steel and vinyl floors. Brush your teeth with baking powder for a brighter smile. Baking powder is also used as a key ingredient in many baked goods, including cakes, breads, muffins and pancakes. Despite this versatility, it is not recommended to add baking powder to help thicken a sauce.

The chemical compound found in baking powder is sodium bicarbonate. Baking powder is basically baking soda plus an acid that is activated when it is combined with fluids, like water and milk. Certain baking powders react as soon as they are mixed with fluids while others react once the mixture is placed in the oven.

Baking powder is used in recipes that require the dough or batter to rise in a short amount of time, such as cakes, cookies and brownies. For these recipes, the liquid is added to the baking powder. When you add baking powder to a liquid, such as a sauce, you will not get the same type of chemical reaction. If anything, adding baking powder may interfere with the taste, making the sauce taste bitter or metallic.

If your recipe turned out more soupy than saucy, there are other key ingredients you can add in order to help thicken it up. Starch thickeners, such as cornstarch and tapioca, thicken up and give puddings, pie fillings and dairy-based recipes a glossy sheen. For acidic sauces, use arrowroot. For soups or stews, add grated potato. If you need a quick fix right before dinner guests arrive, but don't want to alter the flavor of the sauce, add tapioca starch.

Another way to help thicken a sauce is to simmer it. Simmering helps reduce the amount of excess water found in the sauce, thus slowly causing the sauce to thicken on its own. To simmer a sauce, follow the recipe as instructed then reduce the heat until only one or two bubbles form. For optimal results, leave the saucepan uncovered. Turn off the heat source and let the sauce stand for one minute before serving.