This Mushroom Barley Soup is a vegetarian take on the classic Beef Barley Soup. This soup is simply wonderful. I mean, really, really good. There are three kinds of mushrooms here, for layers of deep mushroom flavor. The shitake mushrooms have a wonderful, meaty feel in your mouth, and the barley adds a hearty nuttiness with a little bit of chewy. Perfect recipe to try on this cool snowy weekend!