I have just baked the sponges for Nigella's Chocolate Fudge Cake and they have really puffed up (they haven't flattened with cooling either)! What is the best way to ice the cake when this happens and how do I prevent it from happening again? Cheers, Lorna.
If your cake has baked with large peaks in the centre then it is possible that the oven was a little too hot. This causes the outside part of the cake to cook and set very quickly and the centre is pushed upwards in a peak as it bakes more slowly. It can be common if you use a fan oven and you should check your oven handbook for the appropriate temperature adjustments and also the best shelf to use in the oven.
There is also a product called "baking strips" which you soak in water and wrap around the outside of the cake tins. These slow the rate of cooking slightly, giving a flatter top, and can be useful if you consitently get this problem with your cakes. They can be bought from many bakeware stores and on-line. Always follow the manufacturer's instructions when using baking strips.
For your existing cake you can level the tops by trimming them with a knife. A serrated knife (such as a bread knife) is usually best for this. When you ice the cake, place one layer on a plate with the trimmed top up. Spread some icing over and then put the second layer on with the trimmed top down. This should help to level out the cake and give a flat top for icing.