I want to have the bottom layer of my cake to be half butter cream and half fondant. I want the buttercream to be showing on the bottom half of the cake and fondant over the top and draped over half the layer but with a scalloped or curvy design on the bottom edge of the fondant. the cake is also a topsy turvy cake. how can i put the fondant on the cake and then cut the design without messing it up?

Cut the scallop design before draping the fondant over the buttercream iced cake. Roll out your fondant, place a dummy or cake pan the same size as your tier on the fondant. Cut the scallop pattern. Make sure you cut the pattern pretty wide because the scallops will squeeze close to one another when you drape the fondant.

see i was thinking to cut the design before i put it on the cake but its gonna be a slanted cake so that is going to be hard to get a dummy for and my MMF is usually pretty stretchy and doesn't hold its shape too well when i pick it up and place it on the cake.

If you can, freeze the bc cake for a bit so at least the buttercream cake is firm while you're working. I would make a template out of wax paper. Place wax paper over BC cake, use a pencil to outline the scallop, remove and use pattern to cut fondant. It will stretch a little but it's a Topsy, they're not supposed to be perfect

i like the freezing idea. i hadn't thought about that. you know, i work with CAD and i might be able to lay out the template in my computer program and print. the whole slanted thing kind throws things off a bit but i might be able to do that! thanks.