Hi Julie, sorry I don't know how they have done it but by the look of it I think its fondant.
Hope someone can give an idea how to do it.
IT looks like it would be like how fondant swags are done, but obviously just straight around the edges/bottom.
I also thin k it is fondant wrapped around in several layers.
I'd guess fondant ribbons, starting at the top and building to the bottom
I think I take that back. Since the edges looked rounded, a large swag wrapped around.
Meh, either will work.