A cake sinks when the internal network that holds gas bubbles fails to set before those gases expand and collapse. Structure depends on protein coagulation and starch gelatinization; if those processes lag behind rapid gas expansion cake centers collapse as they cool. Harold McGee, author of On Food and Cooking, explains these basic chemical and physical relationships; America's Test Kitchen at Cook's Illustrated and King Arthur Baking Company each describe practical consequences in home baking guides.
Common causes
Too much or too little leavening can both cause sinking. Excess baking powder or baking soda produces large, rapid gas expansion that the batter’s fragile matrix cannot support. Too little leaves a dense cake that may slump as it cools. Incorrect oven temperature is a frequent problem: an oven running too cool lets bubbles form and grow without the exterior setting, while an oven that’s too hot browns the outside before the interior is fully cooked. Opening the oven door during baking disturbs the heat and reduces internal temperature, a recipe for collapse. Inaccurate ingredient measurement, especially of sugar and liquid, affects batter viscosity and how well it traps and supports gas. High-altitude environments change air pressure and gas expansion; King Arthur Baking Company provides detailed altitude adjustment guidance because a recipe that works at sea level may fail on a mountain.
Techniques to prevent sinking
Measure carefully and use an oven thermometer to confirm actual temperature rather than relying on the oven dial; America's Test Kitchen recommends this as a basic control for consistent results. Bring ingredients like eggs and butter to room temperature so they emulsify and trap air uniformly. Combine ingredients using the method the recipe dictates: creaming introduces stable air pockets, while overmixing once flour is added can develop gluten that makes cakes tough and uneven. Use the correct pan size and don’t overfill pans; a shallow batter sets faster and more evenly.
Adjust leavening to the recipe and to your altitude. If a cake rises wildly and then falls, reduce baking powder or soda slightly the next time. Check doneness by inserting a thin skewer or cake tester near the center; it should come out with a few moist crumbs but not wet batter. Allow the cake to cool gradually on a wire rack; removing it from the pan too quickly or cooling it in a very cold draft can cause sudden contraction and sinking. For particularly delicate recipes, consider using a water bath or insulating the pan to slow temperature changes so the interior has time to set—techniques recommended in professional culinary texts.
Cultural and environmental factors matter: home ovens vary widely across regions, and humidity influences dry-ingredient weights; professional bakers account for local conditions, and home bakers can adapt by weighing ingredients and making small leavening adjustments. Paying attention to measurement, temperature, and timing aligns baking chemistry with real-world conditions and greatly reduces the chance of a sunken cake.