Well, after careful research and shopping, I decided to purchase a 12′ Lodge Logic Dutch Camp Oven.  I found the best regular price at Farm and Fleet, but it was also on sale there!

The recipe I picked from a Northern Iowa Girl Scout Cookbook called for three sliced apples (I cheated and used my Apple-Corer-Slicer-Peeler) layered in the bottom followed by a package of Gingerbread Mix on top.  I did use cooking spray to coat the lid and oven.

I used my new Charcoal Chimney, and prepared 24 coals.  I placed 16 on top and 8 on the bottom.  In about 45 minutes, the cake had pulled away from the sides of the pan — and it was done to delicious perfection!  Clean-up was easy too, as it did not really stick to the oven — used water only for clean-up!