Step 2: Build a Roasting Pit
Build a fire appropriate to the size of your sheet metal, and position one masonry block vertically at each corner. (Some folks prefer a burner and propane tank in lieu of a wood fire.) Place the sheet metal on top of the masonry blocks just as the flames begin to die down. Sprinkle a few drops of water on the metal—if the water sizzles, you’re ready to go. Add oysters in a single layer.