Preparation:
Heat butter in a medium pan over low heat; add onion and mushrooms and cook gently until soft. Add the stock and herbs, bring to boil, add the potatoes, reduce heat and cook, covered, for 30 minutes or until potatoes are tender. Cool. Discard the bay leaf and thyme.

Place soup mixture in batches in a food processor or blender. Process or blend for about 30 seconds or until the mixture is smooth. Return the soup to the saucepan, add the cream and reheat gently. Serve with a little freshly chopped parsley and some good French or Italian bread.