Russian Mushroom and Potato Soup

5 tbsp. butter, divided
2 leeks, chopped
2 large carrots, sliced
6 cups chicken broth
2 lbs. potatoes, peeled and diced
1 lb. fresh mushrooms, sliced
1 cup half-and-half
2 tsp. dried dill weed
2 tsp. salt
1/8 tsp. ground black pepper
1 bay leaf
1/4 cup flour

Melt 3 tbsp. butter in a large saucepan over medium heat. Mix in leeks and carrots and cook for 5 minutes. Pour in broth. Season with dill, salt, pepper and bay leaf. Mix in potatoes, cover, and cook for 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 half-and-half and flour until smooth. Stir into the soup to thicken.