you take it out to room temperature. I always see people that have mousse filling or other perishable fillings that have to be put in refrigerator or they will go bad. when you take cake out wont the cake settle? I was thought that in order to prevent the dreaded cake bulge you have to let the cakes settle out overnight or put a ceramic tile on top for a few hours. if your fillings are perishable and have to be refrigerated how do you make sure that you wont have the cake bulge once the cake gets to room temp?
You let the cake settle in the fridge. A lot of people will also use a thickened buttercream to make the icing dam.
or use the best option: chocolate ganache to cover your cake!!!