Why do cookies go flat in baking?

1. Too much leavening agent:

* Baking soda: If you use too much baking soda, it can react too quickly and create large air bubbles that collapse as the cookies bake, resulting in flatness.

* Baking powder: Similar to baking soda, too much baking powder can lead to over-expansion and subsequent deflation.

2. Overmixing the dough:

* Overmixing develops the gluten in the flour, which makes the dough tough and less likely to rise. This leads to flatter cookies.

3. Incorrect baking temperature:

* Too high: A temperature that's too high can cause the cookies to bake too quickly on the outside, trapping the moisture inside and preventing the dough from spreading. The result is a flat cookie with a puffy center.

* Too low: A temperature that's too low allows the cookies to spread excessively before they set, leading to flatness.

4. Using the wrong type of flour:

* Cake flour: This flour has a lower protein content and produces less gluten, leading to a softer and more tender cookie that can spread more easily.

* All-purpose flour: Using all-purpose flour can result in flatter cookies than using a flour designed for cookies, like cake flour.

5. Thin cookie dough:

* If your dough is too thin, it's more likely to spread out and become flat during baking.

6. High-sugar content:

* Sugar also contributes to the spread of cookies. High sugar content can lead to cookies that are thin and flat.

7. Incorrect baking time:

* Baking cookies too long can cause them to overbake and become flat and dry.

8. Adding too much liquid:

* Adding too much liquid to the cookie dough can make it more runny and prone to spreading, resulting in flat cookies.

9. Using a hot baking sheet:

* A hot baking sheet can cause the cookies to bake too quickly and spread excessively, leading to flatness.

Tips to Prevent Flat Cookies:

* Use the correct amount of leavening agent: Follow the recipe carefully.

* Mix the dough just until combined: Don't overmix.

* Use the proper baking temperature: Check your oven temperature with a thermometer.

* Use the right type of flour: Use a flour designed for cookies, such as cake flour.

* Chill the dough: Chilling the dough allows the fat to solidify, which helps prevent spreading.

* Use a cool baking sheet: A cool baking sheet helps ensure the cookies bake evenly.

* Bake cookies in batches: Don't overcrowd the baking sheet.

* Don't overbake: Remove cookies from the oven when they are slightly soft in the center.