I recently baked the golden vanilla cake from King Arthur FLour's website. It baked nicely, and looked really nice. However, when I was at my cake decorating class, I had to level and torte that cake, and for the life of me, I could not get my cake leveler to go through the cake! It just bounced off and would not go through the cake, no matter how hard I pressed, or sawed. I eventually resorted to using a serrated knife, but even that was incredibly difficult to cut through.
Is there something I did when making the cake? I know I used a 9 inch pan instead of the 8 inch it asked for, but that was the only change I made. Or is this just an impenetrable cake?