i have been trying to bake a 12" sq sponge cake today and the cake rised very high and was looking good, then when i looked an hour later it sunk right down and looked raw in the middle even when the knife came out clean. I never opened the door, please help what am i doing wrong?

A heating core (inverted flower nails) may help. 12' square is very large to distribute heat without help of the flower nails

Also, check you oven temp. do you have a thermometer in your oven?

Hi, thanks for the advice, would you use a normal metal flower nail of the wilton website? so you just place in the tin and pour the mixture around it, would it work for all cake sizes from 6" to 14"? my cakes are 3" deep and i am really having a problem cooking them, i have made 5 cakes today and they are just not working. Do the heat strips work?

The regular Wilton flower nails work fine. I always use parchment, so I stick the nail up through the paper, then arrange it in the pan. However, I often forget, so I just push it down firmly agains the bottom of the pan-no problems.

They will help with a 3' pan. The most likely won't stick out the top, so that can help when you invert the cake to take it out of the pan.

Other wise, you need to use a bit of care to invert the cake so the nail is free to push through the rack (or between your fingers), then you can pull it out from the bottom and re-invert the cake to cool.

hey thank you very much for the help, i will have to give that ago. Do you use the bake even strips? would these help with 3" cake pans?