This simple trick will determine if your baking powder still works

When it comes to baking, you do everything right. You let the butter soften to spreadable perfection, you add dry ingredients to wet at a gradual pace, and you keep an eye on your beautiful stand mixer as it creams the batter instead of watching television. But despite your best intentions, your cookies and biscuits are coming out more "flat" than "flattering."

It's not your technique that's the problem, it's the ingredients. Namely one: your baking powder.

Baking powder, a combination of sodium bicarbonate (the same substance that makes up baking soda) and one or more acids. The reaction that occurs when baking powder comes in contact with liquid causes carbon dioxide to be released, which leavens the mixture. "Double-acting" baking powder, which is the most commonly available baking powder, contains two acids: one that reacts when in contact with liquid and one that reactions when heated in the oven.

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But like any dried good or spice, baking powder loses its potency and power over time, especially when exposed to moisture or heat, which weakens its strength as a leavening agent. While stale baking powder isn't awful-tasting or harmful, a lackluster baking powder yields cookies that are flat and dense instead of round and fluffy.

If you haven't bought a fresh can recently, you can check the freshness of your baking powder with a very simple test: Mix one cup of hot water with 2 teaspoons of baking powder. If there's an immediate fizzing reaction that dissipates all of the powder, you'll know it still works. If there's no bubbling, the baking powder is no longer potent and needs to be swapped out. (The baking powder reacts much faster in hot water than in cold water, so for a more accurate reading, be sure to use hot tap water.)

The bottom line: for light, fluffy baked goods, replace your can of baking powder once every six months.

Get this recipe:Diner-Style Buttermilk Pancakes

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