Tips for dealing with finicky white chocolate in cake batter

[margieslocal]

I made a white chocolate cake yesterday (from Donna Hay's Modern Classics Book 2); it appeared as though all the butter fell to the bottom center of the cake and would not bake thru. The cake was super dense and it lost its lovely dome.

I always have this kind of problem when I use white chocolate in cake batter. I take care to gently melt the chocolate and butter so that it doesn't separate, yet it does every time!

Any hints?