Here is the deal. I have a white cake base with white fondant draped on top of it. I have a 12in. round that needs to sit on top of the base. The cake is chocolate and will have white fondant on it when finished. How should I get the cake to the board with the least mess.
Decorate/Fondant the cake then place on top of the board.
Place the cake on the board then decorate/fondant.
Also do you leave your bottom cardboard under your bottom cake. If so, what do you use to stick the cake bottom cardboard to the fondant base?
I would fully ice and fondant the 12" round choc. cake first...allow it to sit and firm up some and I always leave the bottom cardboard underneath it. I usually stick a square of non slip shelf liner on the bottom board before setting the cake on, it won't move!
As an extra precautionary measure since the bottom is white is to make yourself a collar our of parchment...basically get several strips of parchment or wax paper and lay them all around the bottom board leaving an opening in the center....set your cake down and any residual crumbs that may fall off will land on the paper NOT your white base...then just carefully pull each strip out from under the cake.
I use a cake board or foam core under each layer,including the bottom.Decorate it on the cake board,cut to size,and transfer to the fondant base.I use a little fondant glue to stick it,but I am sure you could use a little water.HTH
Since the board is white, here's what might help you......
I would just go ahead and decorate the cake with the fondant, leave the bottom cake board the chocolate cake is on. Then just transfer with your big pastry knife or large hamburger spatula to the white cake board base.
But before you put the cake on the white base board, put some double sided tape(the white kind) put some strips down,, about 4 pieces onto the white base board, then put your fondant cake onto the white base board.
Once you have all your cakes stacked?, then just put a dowl rod thru the middle of the cakes all the way to the bottom of the white board base. You "hear" a difference when your pounding gently the rod into the cake boards.