Why did my cake sink in the middle?

I think one of the worst things that can happen after baking a cake is when it sinks in the middle! But thankfully, understanding a bit more about the science behind baking can give you a little more insight into where you may be going wrong.

1 – Your ratio of ingredients is incorrect

When it comes to baking, balancing your ingredients is key. If you have too much liquid or too much fat in your cake batter, this can result in a cake with a weak structure which can cause it to sink in the middle.

Bottom line – use a scale when it comes to measuring your ingredients as opposed to cup measurements. This is because cup measurements can sometimes be inaccurate, particularly if you live in a different part of the world compared to the author of the recipe you’re trying to recreate. That’s not to say you can’t get away with using cup measurements (I still provide them in my recipes and many people use them with success), but if you’re noticing your cakes are consistently not coming out the way you’d like, then a scale might be the solution to your problem 🙂

2 – Your cake tin is too small

Most recipes will tell you which size cake tin to use and how many you need. So for example, for most of my recipes I use two eight inch cake tins and I state that in the recipe card. Now if you decide to use smaller sized cake tins, so for example six inch cake tins, or you decide to put all of the batter into one cake tin as opposed to two, then you need to make sure that you’re adjusting your recipe.

This is because too much batter in one cake tin may result in the weight of the batter being too much for the cake to support, causing the cake to collapse and sink in the middle as it bakes. This is especially true for cake recipes which have a more softer, delicate structure to them, which many of my cake recipes do.

What I like to do to make sure I don’t have too much cake batter in one cake tin is I look at the height of the amount of batter that’s placed into the original cake tin, and make sure I do not exceed that height no matter what sized caked tin I’m using. So for example, in my vanilla cake recipe my batter is just under about 1.5 inches high (when placed in two 8 inch cake tins), so now if I decide to place all of my batter into one larger cake tin as opposed to two cake tins, then I’ll make sure that my batter isn’t higher than around 1.5 inches.

3 – You’re undermixing your cake batter

Undermixing your cake batter can be a problem, particularly if your recipe requires you to hand mix your dry ingredients in at the end. This is because under mixing the cake batter doesn’t allow the ingredients to incorporate well enough, which can result in uneven baking. Undermixing can also mean that not enough gluten has been formed to support the structure of our cake, which can cause it to collapse.

4 – You’re overmixing your cake batter

Overmixing your cake batter can also cause your cake to sink and collapse. Now I know this can be really confusing – am I overmixing or undermixing?! But one of the key things here which helps determine whether it’s one or the other, is when it comes to over mixing it’s usually referring to the creaming process.

So creaming is when we whip our butter and sugar together to create air bubbles, and this is usually done at the beginning of making our cake better. Now the problem with over creaming is you can create too many air bubbles, which results in a weak structure that isn’t able to support the weight of the cake as it bakes.

Another thing to note is that if you cream your butter and sugar at too high of a speed, this can also create a lot of large air bubbles which then pop as our cake bakes, causing it to sink. As a rule of thumb (unless your recipe states otherwise), only cream your butter and sugar until it’s light and fluffy, which should take no longer than three minutes. Also stick to a medium to medium high speed – no higher.

5 – You’re opening the oven door too early when checking your cake

When a cake is baking, it relies on a precise balance of heat, time and ingredients to rise properly and set. Now if the oven door is opened too early, this results in a rush of cold air into the oven and can cause the temperature to drop pretty drastically. As a result, this causes the cake to stop rising and set prematurely before the structure is strong enough to support the weight of the cake.

As a rule of thumb, I would only recommend checking your cake when at least three quarters of the stated cooking time has passed to prevent it from sinking.

6 – Your oven is too cold

The last reason I’m going to share with you guys, is that your oven temperature may simply be too low. Now this can unfortunately cause a few problems!

So firstly. it can slow down the formation of air bubbles. When a cake is baked in a low temperature oven, the batter will take longer to heat up and the leavening agents will react slowly, producing fewer and smaller air bubbles. What this can result in is a dense and heavy cake which hasn’t risen properly and can sink in the middle as it cools.

Another problem if your oven temperature is too low is your cake is not going to bake in the required time as stated in the recipe. So for example, if your cake should take 30 minutes to cook, it’s not going to be cooked in those 30 minutes if the oven temperature is too low. This can also result in you opening the oven door too early to check the cake without you even realizing.

To combat this problem, I have two tips! First is to check your oven temperature with an oven thermometer. This is going to help you determine whether your oven perhaps runs a little too cold or a little too hot.

Secondly, is determining whether your recipe is using a convection or a conventional oven. I have gone into more depth about this in by uncommon baking mistakes blog post, but basically a convection oven is going to cook your cakes much faster than a conventional oven. If your recipe states that they’re using a convection (or fan forced) oven and you don’t have one, then you will need to increase the temperature by about 15 degrees Celsius to make sure that your cake is baking at the same rate as what’s stated in the recipe.

Conclusion

In conclusion, baking can be tricky and there is ALOT to learn! It’s taken me years of trial and error to understand baking, and I’m still learning. So if your cake sinks, I know it sucks but DON’T GIVE UP! Hopefully the tips above help you better understand what you could perhaps do a little differently next time 🙂

Happy baking!!