I used to do a lot of backpacking back in the ‘70s and ‘80s. At that time, Optimus sold an item called the Optimus Mini Oven. We used this oven on backpacking and canoeing expeditions to bake numerous foods: casseroles, pizza, cinnamon rolls, and cakes of all kinds.
The oven was not available for decades. Apparently, the Swedish company that manufactured the oven for Optimus is making it again and marketing it themselves. There are currently no retailers selling the item in the U.S. I recently purchased one from a company in the U.K. The oven is identical in every way to the original except that the lid is red rather than turquoise. At the size of a cake pan and 1.1 lb. the oven is ideal for use in a small expedition vehicle.
Link to photo of original Optimus Mini Oven:
http://photos.bwca.com/thumbnails/WETCA ... 095733.JPG
Link to present manufacturer:
http://www.omniasweden.com/index.php?id=3958
I purchased my new oven here:
http://www.base-camp.co.uk/Optimus/minioven.htm
The inner pan must be greased, and the stove must be able to make a sustained burn on simmer. The oven can be used on an electric or gas cook stove. In that the hot air or combustion gases circulate to the top and heat the food from above, fuels such as white gasoline and propane are preferable, while leaded gasoline and high sulfur diesel are not appropriate. I personally would stay away from kerosene or diesel altogether.