Chilled summer soup

Description

Melt the butter in a large saucepan and sauté the onion for 3-4 minutes. Add watercress and cook over low heat for 2-3 minutes. Stir in the flour and cook for 1 minute. Remove from heat, gradually add milk and broth. Bring to a boil, stirring constantly, until the soup thickens. Add herbs and cook for 15 minutes. Let cool slightly, then puree the soup in a blender or food processor. Stir in half of the cream and chill in the refrigerator. Serve garnished with the remaining cream, herbs, and sour cream.

Instructions