I'm making a bunny slipper cake for my niece and would like to be as authentic as possible. The furry part is easy, but what can I do to make the inside of the slipper look like velvet/velour? My first thought was powdered sugar, but I'm afraid that will not stay dry and end up looking gooey. Also, is modeling chocolate a good choice for the ears, which stick up? I've never used it before but I can't wait to try it.

Not sure on the bunny slippers velour part but I have used modeling chocolate and love it. Mine stays up for me in cool conditions. It has only drooped in hot weather.

If you want to achive the velvet look, maybe you use some shiny red dusts or maybe airbrush colors with a sheen.

if you're using fondant, then you can buy a common household scrub, minus any cleaning agents, and press that into the fresh fondant...this will give it the flocked look of velvet or velour.

fogot to add that the courser texture of the sponge, the better...even steel wool.