Powdered version of our dried Shiitake mushrooms. Now available in bulk! Our second most popular mushroom, the Shiitake is one of the most versatile mushrooms in the kitchen. Regardless of urban legends, this mushroom is not indigenous to the United States and can only be picked in a mushroom farmer's growing room. They contain protein, carbohydrates, fiber, linoleic acid, Vitamins B2, C, D and minerals.