Penny - from Belton, TX
I recommend using a heating core for any cake larger than 12 inches across. To use, prepare the heating core the same way you do your baking pan - spray or grease both the inside and outside of the core. Fill the core half full with batter; turn the remaining batter into your prepared baking pan and place the filled heating core in the center. Bake according to recipe instructions. Remove the baked cake from the oven; allow to cool in the pan 10-15 minutes. Remove the heating core from the center of the cake; remove the cake from the heating core and allow it to cool completely. Remove the cake from the pan; cool completely. Insert the cake piece baked in the heating core into the cooled cake. Decorate your cake!