I'm going to try my hand at making some shapes out Rice Krispie Squares (namely, a wine bottle).
I'm wondering, though, if I need something between the Rice Krispie object itself and the fondant that I'm using to cover it with. I'm thinking it will look a bit lumpy if I don't, but I'd appreciate your input if you have any on this one.
Under your fondant, you can use buttercream or melted chocolate (which I believe helps to seal a larger piece against breaking apart).
For a smoother texture, some people crush their Krispies before adding them to the marshmallows...others just use much thicker pieces of fondant when covering.