Chorogi, Knotroot, Chinese Artichoke tachys sieboldii
Crosne, also called Chinese artichoke, Japanese artichoke, knotroot and Chorogi is an Asian member of the mint family grown for its unusually shaped edible tubers.
In Japan Chorogi and also referred to as a Chinese Artichoke where it grows wild in Northern China. The word chorogi means "longevity" and is considered to be a sign of good luck.
They were introduced to Europe in the 1880s (first cultivated in France near Crosne, hence the name) and enjoyed popularity until the 1920s. Crosnes du Japon was the given name by Paillieux (of Paillieux and Bois, Le Potager d'un curieux, 1882). Crosnes are still cultivated in Europe and on a limited basis in the United States. Chefs who have used crosnes grown in both countries are said to prefer the flavor of United States product, perhaps due to the richer soil here (in France they are grown in sand).
They have been rediscovered lately and it's popularity has increased here in the U.S. The tubers look like a string of misshapen mottled pearls. They can be eaten raw, in salads, or stir fried, boiled, baked or in soups.
Varied uses include sliced raw and used in salads, pickled, steamed or in stir-frys. Tubers can also be dipped in tempura batter and fried. Crosnes are never peeled.