On Cake Boss he always steams his finished fondant cakes and it seems to make them shiney and glossy. Has anyone done this or know more about why he does it? Or does anyone know how to make your fondant look this way, mine always looks dry and matte. Thanks!

I recently started steaming mine. It helps dissolve any cornstarch/powdered sugar residue and gives the cake a beautiful shine. I purchased a $35 clothes steamer from Target and it has worked great so far with the exception of the occasional water spitting. :p

How long do you steam it for - just a few seconds?
Can you do this with fondant decorations on a buttercream cake or does the entire cake have to be covered in fondant?

I just steam it for a few seconds or until the cake looks "clean". I hold the steamer just below the base of the cake and let the steam rise instead of aiming it directly toward the cake.
Good question about the fondant accents. I probably wouldn't attempt to steam buttercream. I usually brush my accents (such as polka dots, stripes, etc.) with vodka to clean them up. Someone else probably has a more professional answer for you.

Thanks so much!!