I am just starting to get into cake decorating, and have been using box mixes. My cakes don't seem to rise very much, although I'm not sure what to expect. For instance, a 13x9 cake only rises to be about 1-2 inches high - is this right? I put two together with icing between to make my first cake this morning... any advice would be helpful.

The 9/13 pan needs 7 cups of cake batter and a box mix only produces about 5 and 1/2 cups of cake batter. That would explain why your cakes are not rising that much in your 9x13 pan. But if you are baking 2 and putting a layer of icing in between, your cakes should be fine. As long as they are still moist like you want them.

I use two boxes of mix for my 9x13. If I am doing a filling, then I divide the batter up.

I also use 2 boxes and use the left over batter to make a few cupcakes or mini bundt cakes. I have never tried the cake extender recipes from this site, but plan on the next cake I bake.

Thanks so much - I appreciate it!