I have a request for a Leopard print cake to match these napkins:

http://platesandnapkins.com/pan/zanzibar-leopard-print-beverage-napkins.html

Any ideas on the best way to achieve this? I was thinking that painting would be the way to go, but having never done that before, maybe there's a better option out there?!? TIA

I would color the fondant that lightest base color of that napkin. Airbrush or dry dust with petal dust down the middle in a darker shade, and stipple paint those markings with a stenciling brush.

Petal Dust is a great tip...I hadn't thought of that. I probably should have mentioned that this will be a topsy turvy cake. I'm not sure how to stencil over the top edges of the cakes...is that even possible?
What about painting on the spots? Can you paint on top of petal dust?

Not stencil, use a stencil brush. a flat round brish, even a foam brush. You want to free form design those markings. If you look at the edges of some, they have rounded marks, which would be made perfectly with a stencil type brish. Are they called blotters? Stippling brushes...something like that.