Preparation

• Combine the leeks, potatoes, milk, and 2 cups water in a 4-quart pot.
• Bring to a simmer over medium-high heat. Add 1-1/2 tsp. salt, reduce the heat to medium low, and simmer until a potato slice falls apart when you poke it with a fork, about 20 minutes. Remove from the heat, stir in the cream, and let cool briefly.
• 将汤切成汤，最好使用普通的搅拌机并分批工作，每次仅将其填充。
• Strain the puréed soup through a fine sieve. Let cool to room temperature, stirring occasionally (stirring prevents a skin from forming), and then refrigerate until thoroughly chilled.
• Before serving, thin the soup with water if necessary—it should be the consistency of heavy cream. Season to taste with salt. Serve cold in chilled bowls, garnished with the chives.