How do you store a DECORATED cake when you finish the night before. I have put them in a huge storage container to try to keep them fresh, but sometimes that doesn't work either. Is it good for the icing to sit out? Maybe a silly question, but I'm curious?
Mine sit out on the table or counter overnight for delivery the next day. I only use buttercream icing, too. Once the cake is iced, it's sealed, so it will stay fresh. It was explained to me years ago that it's like when Wonder puts the bread in a bag. It sits on the store shelf and in your pantry for days and it's fine. Our icing is like the bread bag. 
If it is a smaller cake, I box it, like a sheet cake or a smaller round. If it is a wedding cake, I take a large lightweight trash liner and cut it open and lay over the top of the wedding cake as long as the icing has crusted. That way it doesn't get any dust on it. Then in the morning I check it one more time for anything else I may want to do, if not then I go ahead and box it for transportation. I box everything. Just think it looks more professional.
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