I just need some input on whether it's better to cover a cake with fondant before or after the buttercream crusts? Also, is it better to use piping gel so the fondant will stick better?
Once BC has crusted you can smooth it out. The smoother the under surface the smoother the fondant. If it the BC is too dry you could spray with water (not soak) so the fonant will stick to it. HTH
I think it depends on how comfortable you are with fondant. I'm learning, so I like the cake COLD when I try to put it on. Mist it lightly with water so it sort of activates again and the fondant can stick to it. HTH ~ cake on!