Why Does My Cake Sink in the Middle? Common Causes and How to Fix Them

If you’ve ever taken a cake out of the oven only to watch it sink in the middle as it cools, you’re not alone. This is one of the most common problems beginner bakers experience and it can be SO frustrating, especially when you’ve followed the recipe carefully.

The good news is this: a cake sinking in the middle is almost always fixable. Once you understand what’s happening during baking, you can stop guessing and start baking with confidence.

In this guide, I’ll explain why cakes sink, what causes it and how to prevent it in future.

Why cakes sink in the middle

A cake usually sinks because its structure hasn’t fully set before it’s removed from heat or disturbed in some way during baking.

During baking, the cake rises as gases expand and the batter sets. If that structure is weakened too early or before it has stabilised, the centre sinks as the cake cools.

Let’s look at the most common reasons this happens.

Common causes of cakes sinking in the middle

Here’s a quick checklist of the most common mistakes so you can see which might be affecting your cake.

• Opening the oven door too early

  One of the biggest causes of a sunken cake is opening the oven door before the cake has had time to set.

  When the oven door is opened:

  • heat escapes

  • the temperature drops suddenly

  • the cake structure can collapse before it’s stable

  As a general rule, avoid opening the oven door before three quarters of the way through the baking time. If you need to check, wait until after this time.

• Incorrect oven temperature

  Oven temperature plays a huge role in whether a cake rises and sets properly.

  If the oven is too hot:

  • the cake rises too quickly

  • the centre doesn’t have time to bake through

  • it collapses as it cools

  If the oven is too cool:

  • the cake rises slowly

  • the structure remains weak

  • it can sink once removed from the oven

  Many domestic ovens run hotter or cooler than the dial suggests, which is why inconsistent results are so common. Learning how your oven behaves is just as important as following a recipe.

• Too much raising agent

  It’s tempting to think that adding a little extra baking powder or bicarbonate of soda will help a cake rise better. In reality, the opposite is true.

  Too much raising agent causes the cake to:

  • rise rapidly

  • form a weak structure

  • collapse once the gases escape

  Accurate measuring is essential. A well-balanced recipe creates a stable rise, not just a tall one.

• Underbaking the centre

  A cake that looks done on the outside can still be under-baked in the middle.

  If the centre hasn’t fully set:

  • it can’t support the structure

  • it sinks as the cake cools

  Skewer tests can be misleading, especially with rich or moist cakes - or even with fresh fruits. I’ve seen this happen most often with rich chocolate sponges or fruit cakes - the batter is heavy, so it needs extra care. A gentle press test and an understanding of how the cake should feel when fully baked are often more reliable indicators.

• Over-mixing the batter

  Over-mixing introduces too much air and develops structure too early in the batter.

  This can lead to:

  • an uneven rise

  • a dense crumb

  • collapse once the cake leaves the oven

  Mixing just until the ingredients are combined helps create a balanced structure that can support itself as it cools.

How to stop your cake sinking in the middle

Here are the key steps that make the biggest difference:

Preheat your oven properly and allow it to stabilise before baking

• Measure raising agents accurately rather than estimating

• Avoid opening the oven door too early

• Bake until the centre is fully set, not just “looks done”

• Allow the cake to cool gradually rather than removing it from the tin immediately

These may sound simple, but together they create consistency and confidence.

Why following a recipe isn’t always enough

Many bakers assume that if a cake sinks, the recipe must be wrong. In reality, most recipes are written with the assumption that you already understand basic baking principles.

Recipes can’t account for:

• different ovens

• different tins

• different mixing habits

• environmental factors

This is why two people can follow the same recipe and get completely different results.

Confidence in baking comes from understanding why things happen, not just what steps to follow.

Once you learn the foundations, problems like sinking cakes become much easier to diagnose and fix.

Want to bake with confidence instead of guessing?

If you’re tired of wondering why your cakes don’t turn out the way you expect, building strong foundations makes all the difference.

Inside Bake Like a Pro, I teach beginner bakers how to understand the baking process so issues like sunken cakes, dry sponges and uneven bakes stop happening in the first place.

You can also start with my Confident Baker’s Checklist, which walks you through the essentials to check before every bake.

Baking should feel calm and controlled, not stressful or unpredictable.

With a little understanding and practice, you’ll start to see more consistent results and enjoy the baking process even more.