Ingredients
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Preparation
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Step 1
For every cup of flour in the recipe, mix 2 teaspoons cream of tartar, 1 teaspoon baking soda, and 1/2 teaspoon salt. Use this right away; it won’t be effective for more than a day or so.
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Step 2
Stale baking powder can ruin whatever you’re making, but old powder isn’t necessarily stale. Here is a simple test: Put 1 teaspoonful in a cup of hot water. If it bubbles a lot, it’s good. If it doesn’t, throw it out.