Sponge cake pimpling

[Prudie]

Can anyone please tell me what I'm doing wrong that causes my sandwich sponge cakes to always split in the centre and burst into a large pimple in the middle. It's a fan assisted oven but I always reduce the temperature to suit. It always happens in the last 10 minutes or so.

[LyndaB]

It does sound as if the temperature is a bit too high. Or perhaps the tin you use isn't the correct size for the amount of cake mix. However, it's not a total disaster, you know. Providing the cake is cooked, just turn it upside down and dredge with a bit of icing sugar - no-one will be any the wiser ;-)

[Meg888]

I think this happens when the cake starts to take on a 'dome' effect during the cooking stage; I was given a tip by a very good cakester, basically don't pre-heat the oven too much prior to putting the cake in - just enough so that it's warm, always put the cake on the bottom shelf as close to the bottom of the oven as you can; then move your top shelf to the top of the oven and put a cold, empty baking tray on it. I've been doing this for a long time now, and have never suffered the split/dome - I don't know how or why it works - it just does!

[Prudie]

Thank you both for answers. It's a packet mix with the specified tin size Lynda so it may be my oven thermostat isn't too good. Meg that's interesting but I wonder how you can calculate cooking time if you put in a warmish oven and then basically sit on it! It's a shame because it spoils the look for me.

[Meg888]

When I put my cakes in, (I only every bake vanilla/choc sponge) I base my cooking times from the time it goes in - i.e. I cook a 9" sponge with 8oz batter in for approx 40 mins - I check first with knife and if it's clear - it's done. They tend to take no longer than recommended in recipes. Another tip, open & close your oven door very carefully, don't yank them open or slam them shut if your cake is still in there!