In a medium sauce pot, melt the butter with the oil and saute the celery and onion for approximately 1 1/2 minutes or until translucent. Add the flour and blend together to make a roux. Add chicken stock and bring to a boil and whisk until it becomes lightly thickened and vegetables are tender Add the heavy cream and blend well together with a mixer.
Add the remaining ingredients and puree soup in a blender in batches. Serve garnished with celery leaves
Recipe Courtesy of Jim Coleman