In a medium saucepan heat butter over moderately high heat until foam subsides. Add mushrooms and
sauté, stirring, until the liquid mushrooms give off is evaporated and the mushrooms begin to brown. Add wine and boil 1 minute. Add 4 cups stock and salt and pepper to taste and simmer 2 minutes. Puree soup in batches in blender and pour back into pot. Add 1 /2 cup cream and simmer for another 2 to 3 minutes. Serve soup sprinkled with chives.