It is bonito or skipjack tuna turned into one of the hardest foods in the world. It is shaped, boiled, cleaned, smoked, sun-dried for months, and then repeatedly fermented and sun-dried for a coupled of years. The final product weighs less than 20% of the original cut and becomes very hard. This drying and the fermentation processes break proteins down to Inosinic acid which is one of Umami. Thankfully it is available in L.A