Is it best to use a cake board a size smaller to put under your cakes ? I noticed my cakes shrink a bit and the same size seems to big. Im using a 6, 10 and 14 inche cake and they will be stacked. I'm using plastic separator plates because the cake is heavy with ganache filling and don't want the cake to warp.

Do I use the single cardboard cake board (uncovered) then attach it to the plastic separator plate or do I need to double up the cardboard in additon to the plastic separator plate. I'm using a 1/2 in base board (the wilton covered one)

thanks

Even when I use cardboard (rarely--I mostly use masonite now, but I still use cardboard for some cakes and have never had a problem--and my cakes are HEAVY) I don't use separator plates, so I can't really tell you the best way to work with those, but no matter what kind of circle I use I use the size for the cake I am making (never smaller) and the difference between the cake and the size of the circle is what I use as my guide for frosting the cake. I simply frost the cake out to the edge of the circle and use the board as the guide for smoothing the sides.