As I said, it's similar to what I did in my early years. We'd find a fallen limb, preferably birch, and hack four 24" sections off of it, then start binding them together with hemp, using small sticks as spacers. We'd fill the void with birch bark and ignite it. Really, we used these as a form of tiki torch for the winter time, but easily roasted a few things over them. Funny though, as for boiling a pot on it to cook with, that never occured to me before watching Ray Mears.