I have a cake to do for Saturday morning. I am filling it with peanut butter buttercream and covering it with ganache. My question is, can I tort, fill and cover it on Thursday night and not refrigerate it. I do not want condensation on the cakes before I cover them with fondant. Or should I refrigerate it and then take it out and let it come to room temp before I cover it with fondant? I know it is sealed after the fondant is on, but not sure about the ganache. I am trying to manage my time better with this cake and have more time to decorate on Friday night and Saturday morning. Thanks for your advice.

Neither the peanut butter buttercream nor the ganache will go bad if you don't refrigerate them. On the other hand, ganache will get rock hard if you do refrigerate it, so my advice would be to leave your cake out. Ganache seals in moisture just like fondant and buttercream does, and a couple of days to let the cake settle and the flavors blend is all to the good, in my opinion. Sounds delish, by the way!