http://www.cakemonger.com/2008/01/franks-donut.html

I am wanting to make a cake with this look but not sure where to start. If it was made from a regular round cake pan, it had to be carved to get into the donut shape. Therefore, do you think the cake is convered in fondant that was then airbrushed to look like the colors and shade of a real donut? I understand the ganache and "sprinkles" on top but I am trying to figure out if this can be done without covering the cake in fondant?!?!?!

I would've said it was two smooth bundts filled, smoothed, and then covered in fondant and airbrushed. Pretty darn cool cake!

You could also use contour pans.