6 medium Vidalia or other sweet onions, outer layers removed
Wrap each onion separately in aluminum foil and place in a 300 degree oven (or in the coals of a fireplace or grill pit) until onions feel tender all the way through, about 1 1/2 to 2 hours.
Heat oil in a large pot. Add leek and celery; cook until softened but not browned. Remove onions from foil, quarter and add to pot. Add chicken stock and sherry. Simmer about 45 minutes. Stir in cream and thyme. Remove from heat.
In batches, puree mixture in a blender until smooth. Add salt and pepper to taste. Garnish each serving with chives and serve.
©Oso Sweet Onions