Baking Coconut Cake Sponges

Our answer

Nieglla's Coconut Cake (from HOW TO BE A DOMESTIC GODDESS) has sponges based on a Victoria sandwich sponge that are flavoured with dessicated coconut. The coconut is soaked in boiling water (from a freshly-boiled kettle) so that it rehydrates and doesn't make the sponge too dry. We would suggest soaking the coconut for about 10 minutes, until most of the liquid has been absorbed, then cooled to room temperature. If the coconut mixture is too hot it can cause the cake batter not to mix properly and this can lead to a greasier, less risen sponge. You should add any water that is left with the coconut into the cake, but if you are not sure, or it looks like a lot of water, hold back some of the water and then add just enough after mixing the batter to give a soft dropping consistency. And make sure that all of the other ingredients for the sponges are at room temperature.

From the description there are two possible causes of the craters. The first is that when the cake batter is transferred into the tins there are air pockets created, particularly at the bottom of the tins. These air pockets expand in the heat of the oven, causing the craters. Once the cake batter is in the tins, gently tap the bottom of the tins on the work surface once or twice to try and eliminate any air. Also don't over-mix the cake as this can lead to extra air being incorporated. The other source could be with the raising agent involved. Self-raising flour has a 'best before" date and after this it may not rise as well, particularly in humid conditions. Also if the extra baking powder was not combined evenly it could explain why the cake did not rise much but craters appeared in the bottom of the sponge. Small lumps of baking powder would generate pockets of carbon dioxide, giving craters rather than an even rise. You could try whisking or sifting the flour, cornflour (cornstarch) and baking powder together before using them.