Cucumber Soup

In a large stockpot set over medium heat, combine the vegetable broth, potatoes, onion, celery, bay leaf and thyme sprigs. Simmer until the vegetables are tender, about 20 minutes. Carefully remove the bay leaf and thyme sprigs and add the cucumbers. Simmer for 5 minutes more. Turn off the heat and use a hand blender to purée the soup until smooth. Stir in the cream and season to taste with salt and pepper. Allow the soup to cool completely, at least 45 minutes, or transfer to a covered container and refrigerate overnight. When ready to serve, stir in milk and serve.