3. Fill in gaps around the size of the sterno burner with gravel, as shown in the photo above.4. When you’re ready to start roasting, remove the lid from the sterno burner (and keep it!). Light the burner according to the package directions.
5. Note: There won’t be a big flame when you light the burner, but you’ll be able to feel the heat radiating off it for sure! When you’ve finished your s’mores roast, replace the lid of the sterno burner to cut off the oxygen supply. Let the sterno burner cool before handling it or packing it up.