These are the dried mushrooms you'll often find sold in bins in Asian markets. The name "black mushrooms" is a bit of a misnomer, since dried mushrooms can be light or dark brown, and even grey. They are frequently speckled. Black mushrooms range in price from moderate to quite expensive. The more costly are often called "flower mushrooms" as they have a thick cap and a nice curl. These are the best choice if you are preparing stuffed mushrooms. However, the cheaper brands are perfectly acceptable for use in soups and stir-fries.