Baking Tips - Why a Cake Sinks in the Middle and How to Stop It

Baking is a wonderful pastime, but constant problems such as cakes sinking in the middle can be disheartening. Hopefully these simple baking tips will give you a better idea of the reasons cakes sink and how to prevent it.

When it comes to cakes there are some, such as chocolate brownies, where it doesn't matter if the mixture has sunk a bit when it comes out of the oven - it just makes for a more gooey and luscious cake.

However there are some, such as sponge cakes where it absolutely does matter, especially if you were planning on serving it to guests (though there ways of recusing a sunken cake and turning it into a show stopper so if you're reading this because your cake has sunk and you need a way to rescue it skip down to the cake rescue section).

When it comes down to it there are 2 main reason why cakes sink:

• Under-cooked
• Not enough structure in the cake

We'll now take a closer look at each of these to understand better how to prevent it from happening.

Cakes cook from the edges in, so the middle is the last part of the cake to cook.

This is why it's possible to have a cake that's burnt on the edges and under-cooked in the middle - and this sort of result is mainly down to the temperature of the oven.

Cakes that sink are generally ones that rise in the first place i.e. those that have a raising agent in them such as sponge cakes. Cakes which don't have a raising agent i.e. those made with plain flour can still sink but the effects won't be so noticeable.

Cakes rise because the raising agent reacts with other ingredients and the heat of the oven to create little air pockets in the cake mixture which expand in the oven. The cake mixture cooks around them and holds it shape, giving a light, fluffy sponge mix.

When you have a cake which rises you ideally want it to rise and cook uniformly.  If your cakes regularly have huge domes so they are much deeper in the middle that at the sides there is a good chance your even is too hot for the cake. This makes sense if you think about it - cakes cook from the outside so the edges will form a crust first, meaning the only place for the cake to rise is in the middle. Cooking for slightly longer at a lower temperature can help to give a more uniform result and prevent the sinkage which occurs when the crust of the cake has set but the mixture hasn't. For example if a cake has a suggested cooking temperature of 180C I will start it for 10 mins at 150C then turn up to 160C.

Always check your cake is cooked, don't just go by visual appearance - though if the cake is pale and you can see the middle wobbling you can take it as read that it isn't cooked

. To check your cake is cooked insert a skewer into the deepest part of the cake at the centre. If the skewer pulls out clean i.e. no mixture sticking to it, the cake is cooked. If there is mixture the cake needs longer. If the cake needs longer but the outside of the cake is looking in danger of burning, turn the oven down by at least 20C - there will be enough heat to cook the cake but it should stop it colouring any more.

Another way to check if your cake is cooked is to gently press the top of the cake with your thumb - if it springs back immediately it's cooked, if not give it a couple more minutes then test again.

 Another reason cakes sink is because the mixture doesn't have enough structure to it.

Cake mixtures are fairly precise, and whereas if you're making roast chicken with garlic and rosemary and don't have any rosemary you can swap it for lemon and still end up with a perfectly good meal, you can't do that with cakes unless you really know what you're doing.

Being a couple of ounces short of flour, or not having enough eggs can be the difference between success and failure when it comes to cakes as without the right ingredients there isn't enough form to the cake. It's like trying to build sandcastles with dry sand as opposed to wet sand - they just don't work.

By the time a cake has sunk it has normally cooled so putting it back into the oven isn't an option.

If the sinkage isn't too bad i.e. it's more of a light depression than a crater just change your design and cover it up. A slight depression means the cake is more or less cooked so you won't get cake mixture running out when you cut into it. Use Butter-icing, cream, cream cheese or other sort of frosting and so long at the top is level after you've applied the frosting no-one will ever know. If you're icing the cake with fondant put extra buttercream in the depression to level it out before applying the fondant.

For more serious sinkages i.e. ones where the middle of the cake looks like it's had a boulder dropped on it the only thing to do is remove the middle. If you have a chefs ring or cookie cutter that is slightly bigger than the sunken part of the cake use that, otherwise use a spoon to dig out the middle. Remember that the only part of the cake that isn't cooked is the sunken bit, the rest is perfectly fine.

Once you've removed the un-cooked part you'll have a cake which resembles a ring. Fill the centre with a mixture of frosting and fruit, decorate the edges of the cake and it'll look like that was what you meant to do all the time - and it's quite likely you'll get asked to make 'one of those great ring cakes' again.

Remember, many great recipes have their origins in mistakes.

Read these other articles to find the answers to the common baking challenges of how to stop cakes rising in the middle and how to stop cakes burning and how to stop cakes rising in the middle.