Why Do Cakes Sink in the Middle?

Baking really is a science. There are a lot of things that go awry when making a cake! One of the more common questions people find themselves asking is “why do cakes sink in the middle?” Or “why did my cake sink?”

image of an underbaked cake layer to help explain the question why do cakes sink in the middle
This cake layer was underbaked, so the center sunk as the cake layer cooled.

I touched on this topic briefly in my cake troubleshooting guide, but I felt like this topic deserved a bit more detail.

While you might think there’s one main cause, there are a few!! A lot of different factors can cause cakes to sink in the middle.

The goal of this post is to help you understand why cakes sink in the middle and how you can prevent it next time. I also share some tips on how to can salvage cake layers that sank.

Culprit #1: The Cake Layers Are Underbaked

The most common reason why cakes sink in the middle is that they’re underbaked.

If a cake isn’t fully baked through, the center doesn’t have a chance to set and it will sink. This creates a doughy, dense texture in the center of your cake layer.

How To Prevent This Next Time:

Bake your cake layers a couple minutes longer! Or if you’re unsure if the cake is baked through, check with a toothpick. The cake is ready when the toothpick comes out with a few moist crumbs.

Culprit #2: Too Much Leavening Agent

The third possible culprit is too much leavening agent, or the wrong type.

Too much leavening agent like baking soda or powder can cause a cake to rise too high too quickly. The gas from the leavening agents builds up and escapes before the cake bakes through in the center. This causes the center to collapse and makes your cake layers sink in the middle.

A little goes a long way when it comes to leavening agents, so it’s imperative you precisely measure them! Always level the top of the spoon with either the top of the box or a knife to make sure you are using the right amount.

This sounds silly, but it’s also important to make sure you’re using the right leavening agent. Baking soda is about 3x more potent than baking powder, and they are not interchangeable.

image of dry ingredients being sifted into bowl, to follow the recipe and prevent issues with why cakes sink in the middle

How To Prevent This Next Time:

Be sure to carefully read the amount of leavening agents a recipe calls for, and measure them precisely with a teaspoon or digital scale.

There also is a chance that the recipe might be bad! Sadly not all recipes are formulated correctly, and sometimes this can also be the problem. If you try making a certain recipe a few times and your cake is still sinking in the middle, you may want to try a new recipe.

Culprit #3: Oven Door Was Opened / Slammed

While it’s common practice to rotate cake pans part way through baking, this can sometimes cause problems.

If the oven door is slammed after it’s opened, it can cause partially baked cake layers to sink in the middle. If the center isn’t set as the oven door is slammed, it can collapse and won’t be able to rise up properly again.

How To Prevent This Next Time:

If you need to rotate your pans, be sure to carefully close your oven door after doing so. Or if you want to sneak a peek at your cake layers, try to just look through the oven door rather than opening it.

Culprit #4: Your Oven Temperature Is Off

Another culprit is your oven! Unfortunately not all ovens bake accurately. You can run into some serious problems if your oven runs hot or cold.

For example, say your oven runs a bit cool. Even if you bake your cake following the bake time included in a recipe, it won’t bake through in time.

Or if you’re oven runs hot, the cake layers will brown more quickly. This might make you think the cake is baked through. But sadly the cake layers haven’t had enough time in the oven to bake through the in the center.

As the layer cools, the center will sink down because it didn’t have a chance to set.

image of an oven thermometer being used to make sure an oven bakes accurately, to prevent cakes from sinking in the middle

How To Prevent This Next Time:

Test your oven temperature with an oven thermometer.

If your runs cold, adjust the temperature of your oven to ensure it bakes at the actual temperature the recipe calls for. Or if your oven runs hot, adjust it down as needed.

Culprit #5: Using a Different Pan Size

Using a different pan size than a recipe calls for can drastically change the bake time required. It can cause your cake layers to be quite a bit thicker or thinner than the recipe intends.

image of pouring black velvet cake batter into pans

How To Prevent This Next Time:

I recommend using flower nails if you need to bake cake layers that are larger than a recipe calls for.

When I bake large cake layers or sheet cakes, I like to place a few flower nails evenly apart in the center of each pan. This helps the layers bake more evenly and quickly, because they help conduct heat into the center of the cake layer.

image of sheet cake pan with flower nails being used as heating cores to help the cake bake more quickly and evenly

It’s also important to calculate the amount of batter you need correctly. This will help ensure that your cake layers a similar thickness to what the recipe intended.

How To Fix Cake That Sank in the Middle

If you find yourself with a cake sunk in the middle, there are a few things you can do to fix it.

Sunken Cake Fix #1: Level the Cake Layer

The easiest and quickest fix is to level the cake layer. This allows you to cut away the under-baked or raw section, and leaves you with a level, undimpled cake layer. However, this only works the center only sinks a bit.

image of underbaked cake layer that has been leveled, to help answer the question why do cakes sink in the middle

Sunken Cake Fix #2: Pop The Layers Back in the Oven

If you notice that the center of your cake sinks right after you take it out of the oven, you can pop it back into the oven for a couple minutes.

This won’t actually fix the sunken center, but it will help the undercooked center bake through.

Sunken Cake Fix #3: Use Extra Buttercream To Assemble The Cake

If all else fails, you can cut away the undercooked sections and just fill the cake in with a bit of extra frosting.

Buttercream can fix just about anything in my opinion 🙂

Let Me Know What You Think!

I hope you found this post helpful, and that your cake layers bake through fully and rise nice and high from now on ?

If you think your cake sank for a different reason, let me know what issues you’re having in the comments section below. Hopefully we’ll be able to figure it out together!

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4 thoughts on “Why Do Cakes Sink in the Middle?

  1. Thank you for the excellent reminders about how to fix the middle of “sunken to cakes“… Personally, I have had some good success avoiding the sinking process by using flower nails even with 9 inch pans … Thank you for teaching me about this option!

  2. Thank you so much for all of your insight. My question in in reference to the sides. After the bake when the cake cooks it pulls away from the sides and the top edge shrinks inward. I am using an 8in by 2in pan And I measure out the batter.

Let me know what you think!