Cook diced sausage in skillet with 2 tbs butter for 5 minutes.
and cook until soft. Add thyme and sweet potatoes and cook 5 minutes.
liqueur and broth and cover and simmer over low heat for 45 minutes
until potatoes tender. In blender puree soup in batches. Return
to pan and
stir in cream and remaining 2 tbs butter. Warm but do not boil.