Dale, Many years ago my family used to go to mountain man gatherings. One year there were a couple of ladies who demonstrated how native americans would cook soup using hot rocks that were dropped into an animal stomach filled with water etc. It was awesome.
Not that many would care but there is old Mongolian Marmot recipe which basically involves catching, skinning, and cleaning a marmot; stuffing its cavities with hot rocks, and then wrapping it back up in its own skin to steam. Sound pretty good. Maybe toss an onion or some garlic in there?
I probably won't make soup, with hot rocks. I could see tossing one in from the oven to heat soup when the stove is not being fired.
Tonight, I cooked turkey. As I listened to it sizzling on the rocks, I knew that I must once again suffer for my art.