As the title said, I just finished icing a cake with Swiss Buttercream Frosting (9pm). It will be served tomorrow at 11am. Do I need to refrigerate or cover with plastic wrap? No fruit filling. Just frosting in between layers.
AThis may be a little late for you, but here is a link to a discussion on the same question: http://cakecentral.com/t/670887/help-do-you-have-to-refrigerate-swiss-meringue-buttercream.