I am making a cake that is white on top and blue on the sides.
The original picture I got the idea from was made with fondant. But I need to make this with BC.
Is there a good technique to do this?
Easy...crumb coat your cake as usual. Use blue colored crusting buttercream around the sides (not on top). Make sure that it comes up to the top sides though. Then do white crusting buttercream on top up to the blue edges. Viva till your hearts content as usual. Use your favorite border (like Shells or rope) to hide the "seam" of where the white and blue meet in whatever color of buttercream. Let me know if this doesnt make any sense.
Airbrushing is another method. Have all white crusting buttercream. Viva smooth. Cover the top so it doesnt get sprayed and then airbrush the sides blue.