I just made this and it is awesome! It's still on the stove and because I did not have all the ingredients I subbed red onion for leek and fat free sour cream for half & half. It still rocks. Make it your way and enjoy! dannyz
Melt 3 tablespoons butter in a large saucepan over medium heat. Mix in onnion and carrots, and cook 5 minutes. Pour in broth. Season with dill, salt, pepper, and bay leaf. Mix in potatoes, cover, and cook 20 minutes, or until potatoes are tender but firm. Remove and discard the bay leaf.
Melt the remaining butter in a skillet over medium heat, and saute the mushrooms 5 minutes, until lightly browned. Stir into the soup.
In a small bowl, mix the sour cream, milk and flour until smooth. Stir into the soup to thicken. Garnish each bowl of soup with fresh dill to serve.