Mushrooms and vermouth - who knew they'd taste so good together? Very good, broth-based soup where the mushroom flavor really shines, since there's no cream or milk. It's also vegetarian but could be made vegan (substitute olive oil for butter and vegetable broth for chicken broth). We usually have this all year round, but like it especially to start a Thanksgiving or Christmas dinner. Especially nice since you can make it in advance! Adapted from "Colorado Cache".