Oldie Moldy,

I made a Flashing oven that you can use over stove/fire.
For the lid you use a pie tin, but I wanted a way to check on the baked goods, so I cut out a large hole and made a inspection port out of one of the silicone baking sheets.

That's a long way of saying that the high temp silicone pad stays cool enough to the touch that I can use my hand to open and close it.

Cut one bigger than the pie pan and lay between your up/down pans and see if that doesn't keep the earth from scorching?
Weighs zilch and folds up to nothing.