A Little Less Leavening

• Cakes rise because of air bubbles in the batter. As the cake bakes, the gas inside those bubbles expands, making the cake grow. Before the air bubbles become too big, the heat of the oven sets the batter, making it structurally sound, like papier-mache strips hardening around a balloon. These air bubbles form primarily because of your leavening agent, or rising agent -- one commonly used in cakes is baking powder. Using slightly less leavening agent stops your cake from expanding so much -- it may be denser, but it will also be flatter.

The Pan-Switching Plan

• Regardless of shape, there are two types of pan in which you can bake a cake: a dark nonstick pan or a light aluminum pan. While the former makes it easier to remove the cake when you’re finished, it also absorbs heat. This makes the parts of the cake touching the pan set and stop expanding before the part not touching the pan -- the top of the cake, which continues expanding and forms a hump. In contrast, a light aluminum pan reflects the heat away from your cake. This means that the cake expands and sets more evenly, preventing the middle of the cake from expanding out of control. To compensate for the lack of a nonstick surface, line the pan with parchment paper before pouring in your batter.

Take Your Cake’s Temperature

• Though you can use your recipe as a guide for determining when your cake is done, leaving it in the oven longer than necessary can make the center of the cake expand too much and form a hump. Shortly before the recipe says that your cake should be finished, take its temperature in the center using an instant-read kitchen thermometer. Regardless of what the recipe says, if the cake has an internal temperature of about 210 degrees Fahrenheit, it’s ready to come out of the oven.

Perform Cake Surgery

• Because of the way radiant heat is distributed throughout your oven, avoiding the hump isn’t always practical or possible -- even if you adjust your recipe and try new equipment, you may be left with a slight bulge. This is a problem that even professional decorators encounter, and when they do, the typical solution is to simply cut off the hump. Carving off the hump after your cake cools eliminates a negligible amount of food, and if you’re icing the cake, no one will be able to spot this trick. Use a long, serrated bread knife to slice it off.