From Bon Appetit, Dec. 2006 under "All the Trimmings" from Betty Rosbottom. This soup looks terrific in the photo. You can make this a day ahead of serving. Just cover and chill. Heat soup over medium heat, stirring occasionally; do not boil. Ladle soup into bowls. Garnish with reserved mascarpone. Sprinkle with chopped chives and serve.