Oita prefecture represents 40% of Japan's dried shiitake production, and has been growing shiitake since around the early Edo period (1603 - 1868). Oita's climate and abundant natural environment make it ideal for growing shiitake, and they are grown in a way that uses no chemicals or additives, just the natural sawtooth oak logs on which the shiitake grow, which are provided through cooperation with local forestry departments. This organic growing process may take longer than other methods, and depends heavily on the weather throughout the year, but it produces succulent mushrooms that are full of flavour.
In fact, Oita's shiitake are so good that in Japan's annual dried shiitake contest (yep, that's a thing!), Oita's Shiitake Agricultural Cooperative (also known as OSK) has won first place in the group category an amazing 48 times out of 62, including a 16-year win streak! At the Grand Sumo Tournament, the winner even wins a handmade trophy full of premium kouko shiitake grown in Oita. Thanks to this, Oita's shiitake are well known all around Japan, but we can try them in the very prefecture they come from! They are used in a wide variety of dishes, from nabe (hot pot) to chirashizushi, and a local speciality is even shiitake tempura.