good to hear of your experiments.  we never tried putting a whole pan in in the bag.  We have always just floated the bag in the water.  then we spoon out the baked goods. yum, who cares about the shape of your brownies.  

If you have one of the cooksets where the pan sits on top of a pot you can cook corn bread that way.  We fill the pot with a little water, then set the dual purpose pan/lid for the pot on top.  The pan then has its own lid.  we place hot coals on the lid.  a makeshift dutch oven...  works great.