Sweet Potato Vichyssoise



  1. In a Dutch oven cook leek in hot butter until tender.
  2. Stir in remaining ingredients except half-and-half, sour cream and chives.
  3. Simmer, covered, for 10 to 15 minutes.
  4. Using an immersion blender, process until smooth.
  5. Transfer to a bowl.
  6. Stir half-and-half into potato mixture.
  7. If necessary, add more half-and-half to reach desired consistency.
  8. Chill for at least 4 hours.
  9. Serve with sour cream and chives.