4 tbsp. butter
2 sm. onions, chopped
1/2 lb. mushrooms
1 tbsp. flour
4 c. chicken stock
1 tbsp. lemon juice
1 c. cream
3 tbsp. fresh mint, chopped
2 egg yolks
3 tbsp. sherry
Salt, pepper, herbs

Cook onions and garlic in butter for 5 minutes. Mince mushrooms, add to onions and cook slowly 10 minutes. Add lemon juice and stir in flour. Add stock and bring to a slow boil. Puree in blender. Add cream and mint. Beat yolks with sherry. Do not boil.