My mouth is watering just thinking about it:

Ingredients

1/2 lb fresh mushrooms, sliced
1 onion, finely chopped
1 clove garlic,minced
1/4 tsp nutmeg
1/2 tsp dried tarragon
3 T butter
1/4 c flour
2 cans beef broth
1 c sour cream
1/2 c half & half
1/2 c evaporated milk (I usually use regular milk because I never have evaporated around the house.)
1 tsp lemon juice
dash hot pepper sauce
pepper (salt, too, but I find the beef broth usually has enough salt in it.)

Method

1. Saute the mushrooms, onion, garlic, tarragon, and nutmeg in butter until tender.
2. Stir in flour until smooth.
3. Gradually add broth; bring to boil, stirring constantly.
4. Reduce heat to low; slowly add sour cream. Cook and stir until smooth.
5. Stir in cream and milk.
6. Add lemon juice, hot pepper sauce, pepper.
7. Heat through, but do not boil.