Burton products makes some devices.  I have the following one.
http://www.12vautotech.com/stove.html
 Current is ~16A/8A.  Clips closed easy cleanup with the breadloaf
pans  Not suitable for engine off use because of the draw.

Perhaps a wire basket just over the muffler?  Or:

http://en.wikipedia.org/wiki/Manifold_Destiny_(cookbook).

Our fave was done sausage and sauerkraut (typical westfalian food).

On Mon, May 3, 2010 at 7:06 AM, Loren Busch <starwagen@gmail.com> wrote:
> Ran into this while snooping around the Internet for something else
> http://www.roadgiant.com/roadprorpsl-35012-volt15quartslowcooker.aspx
> It caught my attention because some time back there was some discussion on
> using a small 110v AC crock pot, w/inverter, while driving and then having a
> hot dinner waiting when you stopped at night.
> this just might do the job. �If I were using it I'd only use it while
> driving, it's going to suck a lot of juice if the engine is off.
> That site has several other such 12v cooking appliances.
>