I need a chocolate cake with white fondant. Do I have to use white buttercream or can I use chocolate buttercream - will it show through the white fondant?
I cover chocolate buttercream with white fondant all the time. You just need to have a good boarder to cover any choc smudges that may be left behind when you cut the fondant away, and always make sure your hands are clean clean clean! If you have any amount of choc on your fingers, and then try to smooth, your fondant will have a few small 'dirty' looking smudges.