Experimental Earth Oven 3. After two days of baking, the oven is opened. Here the upper packing layer is scrapped back, exposing a large sotol "head." As it turned out, the neophyte earth oven chefs had used too much fuel and rocks relative to the food load and charred much of the food. The same thing occasionally happened to prehistoric cooks, resulting in the charred food remains that archeologists sometimes find. Photo by Steve Black.