Set log of wood on fire.

Combine water and salt in a pot to make seawater. Add in kombu and bring to a boil. Add bonito and turn off heat.

Extinguish fire on log and place your choice of fish directly on log for about 30 seconds to 1 minute on each side. Make sure the middle of the fish stays raw.

Take fish off the log, slice thinly, and then place in seawater.

Take fish out, squeeze lemon on it, and enjoy.