The Dangers of Over-Mixing

• Don’t let another batch of cookies go flat on you. One possibility is that you over-mixed your ingredients. Cream the butter and sugar to fully combine the two into a smooth mixture, but don’t beat for much longer than 30 seconds or they end up rising too much -- and then falling -- in the oven. As soon as the butter and sugar are combined, put down the stand mixer or whisk. Over-mixing at any stage can also result in tough cookies.

Sensitive Dough

• If a heavy hand with the whisk isn’t your problem, retrace your other baking steps to figure out other things that may have gone wrong. Many factors may interfere with a lightly risen, perfect cookie. Make sure you’re baking cookies on parchment paper or a silicone baking mat -- not a greased surface that the cookies will cling to. Refrain from opening the oven until your cookies are almost done to avoid deflation from a sudden temperature drop. Additionally, it’s a good idea to chill your dough before baking.

High-Altitude Cooks

• If you live at high-altitude, thin air could be the culprit. Adjust the recipe for your elevation. For example, you may need to add slightly less baking powder or baking soda, sugar and fat, and slightly more flour, liquid and egg. Incorporating acidic ingredients like buttermilk or a bit of vinegar can also help. Finally, some high-altitude adjustments call for a slightly shorter baking time at a slightly higher temperature.

Flat Cookie Ideas

• Hopefully, next time your cookies will rise perfectly. In the meantime, you have a dozen or more flat cookies to deal with. Instead of throwing them out, get creative. Grind them up in the food processor and press them into a pan to make a crust for a cheesecake, chocolate cream pie or ice cream pie. Alternatively, crumble them up and use them as a layer in an ice cream sundae or dessert parfait.