Why You Shouldn't Let Your Cake Batter Rest Before Baking

Baking a cake from scratch is no easy feat, but understanding the science behind it can make you a more careful baker, which will certainly give you a better chance at success. For instance, you might not think twice about leaving your cake batter out on the counter for a few minutes before putting it into the oven to bake, but with a little bit of ingredient knowledge, you'll understand why this is a major mistake. Your leavening agent activates the second it touches a liquid, so if you let your cake batter sit, you'll be left with a dense, flat cake rather than the classic and decadent cake of your dreams.

Most cake recipes require you to prepare your wet ingredients in one bowl and your dry ingredients in another. Depending on the flavor of the cake, your wet ingredients will likely include butter, eggs, oil, vanilla, and milk. Your dry ingredients will probably consist of flour, sugar, baking soda or baking powder, and salt. These wet and dry ingredients are kept separate until the very last step of the preparation process for a few reasons, but perhaps the most important reason has to do with the leavening process.

When your leavening agent — either baking soda or baking powder — touches liquid, the batter begins to expand and release gas. The more you mix it, the more your gluten develops, which is why you should also avoid overmixing. When you let your cake batter sit out on the counter, it slowly loses its rising power, which means your cake won't rise as much in the oven as it's supposed to.

This is one of the most common mistakes people make when baking cake, but thankfully, it's an easy one to avoid. Just remember to grease your cake pan and preheat your oven at the very start of the baking process so that you're all set up and ready to go after your batter has been mixed. Preheating the oven beforehand will also allow for even temperature disbursement, which gives your cake a better chance at cooking evenly.

In addition to preparing your materials, be sure that your leavening agent is still active. When baking powder expires, your cake will be flatter and more dense, even if you put the cake batter into the oven immediately. Since humidity and improper sealing can have an effect on baking powder's activity, the expiration date isn't always your best bet for finding out if you can still use it. However, there's a test you can use to see if it's still active. 

Simply pour a quarter cup of boiling water over a half teaspoon of your baking powder. If it begins to bubble, you'll know that it's still active and will cause the desired reaction in your cake batter. If it remains flat, however, you'll know that it's not good to use in your cake. Once you follow these simple tips, it's almost guaranteed that your homemade cakes will improve.