Shiitake mushrooms, as they are commonly known in the United States, have a distinctive earthy taste and meaty texture. More flavorful than fresh, dried shiitake need to be soaked in water for approximately 20 minutes, depending on their size. Once reconstituted, the mushrooms are rinsed to rid them of dirt They cannot be eaten raw and must be cooked. The soaking liquid can be used in soups and sauces, and keeps in the refrigerator for several weeks. Dried shiitake is now available in many supermarkets and shouldn’t be a problem to find. You can substitute the fresh variety.