I made this cake but I doubled the recipe to make a larger cake. It was very good except it was just slightly drier than I wanted. I may have overcooked slightly but not sure. I was wondering if when doubling the recipe I needed to adjust something a little differently such as the baking poweder or something. I read something about that somewhere but not sure how to calculate. I want to use this for a wedding cake but don't want it to be too dry. Any ideas?