Macadamia shell cookstove producing high quality biochar

A simple cookstove built from locally available tin cans burning old macadamia shell produces a flame without smoke for cooking - but also a very high quality biochar/charcoal - ALL the fuel is from a living tree without causing deforestation.

[@grantwatson1148]

how do you make the charcoal?

[@galgalimeyes91]

there no tutorial ?