What is a common mistake in cookie baking?

Not measuring ingredients accurately is indeed a common mistake in cookie baking and is crucial for achieving the desired texture and flavor. Precision in measurements ensures that the balance of dry and wet ingredients is maintained, which directly affects the dough consistency, spread, and overall finished product.

When ingredients are not measured precisely, it can lead to several issues. For instance, too much flour can make cookies dry and crumbly, while too little can cause them to spread excessively and lose their shape. Similarly, the incorrect ratio of sugar, leavening agents, and fats can impact cookies' taste and texture, resulting in a final product that is not what was intended.

In contrast, while using cold butter may affect the spread of cookies, it is a technique used in some recipes to achieve a particular texture. Baking at a low temperature can impact the cooking process but is not inherently a mistake if the recipe directs it. Using old baking powder is also an issue, but it primarily affects the leavening process rather than the fundamental balance of ingredients in the cookie dough. Therefore, the accurate measurement of ingredients is widely recognized as essential in baking, especially for cookies, leading to the conclusion that it’s a common mistake for bakers.