Espina is considered a nuisance tree in the Chilean countryside; it grows prolifically and has gnarly tenacious roots that defy extraction…not to mention thorns sturdy enough to puncture tires.
Using a process that hasn’t changed in centuries, farm hands pile espina wood on bare ground on the edges of newly cleared fields. Then they make a slurry of water and clay and build an igloo-like structure over the pile with walls 6 to 8 inches thick.
An opening, which is later blocked with stones and mud, is preserved so fires can be lit in the wood pile. With shovel handles, vents are poked around the periphery of the oven and a chimney is created in the top and “decorated” with small pieces of charcoal.
The fires burn and smolder for three or more days. Then the vents are plugged, starving the fire of oxygen. Finally, the charcoal is harvested. Sometimes, before the elements reclaim the oven, it is used to barbecue meat. (Nancy will share another Chilean BBQ invention–unique in the world–in this space in a few weeks.)