It's Time To Use That Sourdough Starter For Chewy Chocolate Chip Cookies

You're getting ready to bake a fresh batch of homemade chocolate chip cookies, and you notice the foamy and fluffy sourdough starter you made not long ago in your pantry. A fun thought pops into your head. What if you use some of that sourdough starter to make the cookies?

Well, you definitely should, as it's time to use that sourdough starter or discard as an ingredient to upgrade your chocolate chip cookies. The reason is that adding active sourdough starter or sourdough discard to your cookie dough will make the cookies soft and chewy. Plus, since sourdough starter is tangy, your chocolate chip cookies will have a slight tang that's quite pleasant, like snickerdoodles. And, by using up sourdough discard, you are contributing to reducing food waste.

Sourdough starter is, in essence, a fermented mixture of 1:1  flour and water in weight. It is what we typically use to make sourdough bread. A sourdough starter must be fed to keep it active, and every time you feed it, some of it gets discarded. This is known as sourdough discard. Sourdough bread results in more of a toothsome bite and chew than typical white bread made with yeast. Thus, chocolate chip cookies made with sourdough starters tend to be chewier, soft, and tender. However, when you add a sourdough starter or discard in your chocolate chip cookie dough recipe, it will change your recipe and replace some of the flour and wet ingredients, like butter or egg. 

As you adjust your recipe, remember the balance of wet and dry ingredients in the cookie dough and consider the makeup of the sourdough starter. So let's say you're adding 100 grams of sourdough starter or discard to your favorite chocolate chip cookie recipe. Sourdough starter is made from about 50 grams of flour and 50 grams of water; thus, you should subtract about 50 grams of flour and 50 grams of liquid from your ingredients. Subtracting the flour part is easy. Compensating for the added wet content from the sourdough starter or discard is trickier since cookie recipes normally don't include much (if any) water or milk. 

However, one medium egg weighs about 50 grams and is a wet ingredient. You can try removing the egg or at least the egg white from your cookie dough or browning the butter to reduce its water content and compensate for the addition of the sourdough discard or starter. So, although some food science and adjustments are involved, it's worthwhile to use a sourdough starter or discard to make your next batch of chocolate chip cookies, especially if you enjoy soft and chewy treats with an alluring tang.