I had to make this twice as the first time was a total failure. Hopefully this review will save you from wasting your time and ingredients as the other reviews were only somewhat helpful. First, forget about the flower nail in the deep part of the cake. It doesn´t work. That part of the cake still came out like goo even when tested for doneness. What you will need is the heating core Wilton sells to be used when baking cakes over 10 inches in diameter. Just follow the instructions for its use. A cake nail does not have a big enough circumference to help the deep center of this pan bake properly. Make sure you use cake release or PAM with flour, etc. and coat the pan well, including the edges around the top. Now the towel idea is great. I got two dish towels really wet, almost dripping, rolled them and placed them under the shallow part of the mold, to fill that gap there, while wrapping the ends toward the deep part of the mold (although they did not wrap all the way around), being sure to keep them from allowing the mold to make full contact with the cookie tray. Yes, make sure you put something under this mold as the batter will overflow at the deep end. I weighed my batter and it takes about 1390 grams of batter to make this cake come out correctly. I had 2 thermometers in my oven on opposite sides, one high, one low and both read 350F. I rotated the pan every 25 minutes with a total cooking time of 67 minutes. Remove the heating core and allow to cool with the cake. You will need to trim around the edges at the deep end (top) to allow the cake to release after it rests 10 minutes. Use a spatula on the inside edges to loosen the cake before turning out. Do the same with the heating core. When everything is cool place the part cake from the inside of the heating core back into the hole in the deep (top) part of the cake, trim the edges as necessary and you´re ready to frost.