I made this cake in two 9 inch round pans, so I increased the recipe per layer 10% over the heart pan to account for the larger pan, then doubled it for the two pans. That’s a factor of 2.2. This worked nicely for the cake, but I learned an important lesson about this recipe for the frosting…the frosting as listed doesn’t cover the cake! I didn’t realize that the blob of frosting in the middle of the heart in the photograph in RHC is all you really get; I thought that was merely artistic license showing a cake in the process of being frosted, not the completed cake. If you want to cover two 9” round cake layers, you need to use a factor of 4.4 for the frosting. Even at that, the frosting wasn’t super thick, although it was adequate for this type of cake.
I’m not that fond of cream cheese or white chocolate, so I thought the cake was just fair, but everyone else seemed to love it.