Shiitake mushroom. Indigenous to the forests of China, containing eritadenine which helps to lower blood cholesterol levels. They are found growing on tree trunks in the Far East and have white stems and brown fleshy caps with white ruffled gills. Mushrooms with the edges slightly tucked under, rather than spread flat, are the best ones. Fresh shiitake are grilled and are used in soups and miso, as well as in deep-fried, nabe and custard dishes. Dried shiitake are darker in colour and have an intense, smoky, 'umami' flavour. They are sometimes sold as "winter mushrooms", which are produced in colder conditions and are especially highly regarded. In Russia they are frequently pickled.