If you're out of baking powder you're not out of luck. That's especially true when making a dish like cornbread, which usually contains the kind of tart, acidic ingredients like molasses, vinegar or buttermilk that interact with a simple pinch of baking soda to help the bread rise. Even if your cornbread recipe veers toward the non-tart side of the palate, however, options abound for getting around the lack of baking powder.
Baking soda helps breads rise when paired with acidic ingredients such as buttermilk. For every teaspoon of baking powder you need to replace, add 1/4 teaspoon baking soda to the dry ingredients -- or increase the baking soda already called for in the recipe by 1/4 teaspoon. Cornbread normally contains acidic liquids anyway, but if not, swap out 1/2 cup of regular milk or water in the recipe for 1/2 cup buttermilk or sour milk when adding the 1/4 teaspoon baking soda to the dry ingredients. Another option is to add 1/4 cup molasses to the wet ingredients when adding the 1/4 teaspoon baking soda to the dry ingredients.
Powdery Pinch Hitters
For cornbread and other quick breads reliant on baking powder to rise, combine a few other pantry staples in its place to approximate a commercial baking powder mix. Blend together 2 parts cornstarch, 1 part baking soda and 1 part cream of tartar. Use this mix as a 1-to-1 substitution for baking powder. For example, a cornbread recipe specifying 1 tablespoon of baking powder can be tweaked by using 1 tablespoon of the blended cornstarch, baking soda and cream of tartar mixture. Use additional baking soda if the cornbread recipe calls for it.
If you have self-rising white flour in your pantry, which is sometimes labeled as cake flour, you won't need to run out to the store for baking powder. That's because the baking powder is already incorporated into the flour, often along with enough salt to activate the baking powder. Self-rising cornmeal is also available. If you have one or the other, you won't need another leavening agent, or salt, in your cornbread recipe.
Pan of Attack
Skillet cornbreads are meant to be denser and flatter than those baked in square or loaf pans. For that reason, they don't generally require baking powder or white flour, relying instead on a small amount of baking soda to keep the bread from being pancake-thin. After butter is melted in an ovenproof hot skillet, a simple batter made from cornmeal, eggs, baking soda, salt and buttermilk gets poured into the skillet, and the corn bread bakes for about 20 minutes in a 425 degree Fahrenheit oven.