Known in Japan as gobo, burdock is a slender root vegetable with a rusty brown skin and grayish-white flesh. Cultivated primarily in Japan, it grows wild throughout much of Europe and the United States. Burdock has a sweet, earthy flavor and tender-crisp texture. It's important to choose firm, young burdock, preferably no more than 1 inch in diameter; they will be about 18 inches long. Do not wash the earth-covered roots until ready to use. Store, tightly wrapped in a plastic bag, in the refrigerator for up to 4 days. Scrub before cooking; peeling isn't necessary. Burdock can be thinly sliced or shredded and used in soups as well as with vegetables and meats.