If I ice a cake tomorrow with buttercream icing, will my fondant decorations that I cut out tonight stick? Box says to brush water or more icing on back of fondant. I dont want the decorations to start falling off the cake after. also, I have the fondant pieces in a zip lock bag, will they keep moisture for tomorrow or should I put a damp paper towel in? they are currently sitting in bag on wax paper.

in my experience, fondant decorations do not adhere well to buttercream, no matter what you do. Best to stick with buttercram finishing frosting, use royal icing decorations that have been pre, prepared. fondant finishin, use fondant docorations that u made days in advance and have let set out inthe open to dry. adhere them with a little water.

I use fondant decorations on buttercream all of the time. If your buttercream is crusted I find a little buttercream on the back of the decoration works best to adhere them. Water doesn't always work as well on crusted buttercream. I'm not sure about storing the fondant decorations over night. I've always used them immediately. Hope someone else can answer that question.

I have used fondant accents on butter cream with no problems personally. I have put it on while still soft and after had dried. I did wait till my butter-cream set first tho. Sort of a 'crust like' stage. I use vodka to 'glue' the pieces on. It dries fast. Just brush very lightly with a paint brush on the back side of your applique and then place it. I just posted a pic today with butter-cream and black fondant fringe. It was only attached to the edges of the tiers( about an inch top of cake, and hanging fringes over the sides)..not covering the whole topside. It's the blue and black 3 tier in my pix if you want to take a look. HTH

This is just my opinion but if you've already gotthe pieces cut out I'd just attach them now and be done with it. The more crusted the icing the more difficult to attach. If it's only slightly crusted just a little piping gel and press them SLIGHTLY into your bc. I agree with the previous poster, water on bc can work but you run more risk of the water dripping and remember bc is mostly oil (butter). Oil & water repel, not meld together.

The fondant pieces will be fine in the ziploc bag, but if they're stacked or touching you may not be able to get them seperated tomorrow. They can be dry when you attach but if the design is very big and flat you may not be able to get it to lay down flat around a round cake.