I have tried in the past to stack two tiered cakes 6 in. and 9 in. iced in Swiss Meringue Buttercream using the SPS system. However, when I inserted the plate with the dowels into the bottom tier of the cake, my buttercream cracked horribly and there was no way of covering up the crack. My buttercream was cold, so I don't know if it had something to do with the cracking. So how would one go about stacking a cake iced in SMB using the SPS system so that the buttercream won't crack? Is there a special trick to it? 
Thank you very much for all of your help. I greatly appreciate it.
Thank you very much for all of your help. I greatly appreciate it.
