- Peel and cube the potatoes
- Mince the garlic and the shallot
- Slice the mushrooms
- Chop the chives carefully as they are used for garnish
1. Put the potatoes, mushrooms, garlic, bay leaf, savory, marjoram, and salt and pepper into a medium-size stockpot. Cover with about 6 cups of cold water. Cook over medium heat until it boils, then reduce heat and cook for 20 to 30 minutes.
2. In a separate small saucepan, heat the cooking oil over medium-high heat. When hot, sprinkle in the flour and shallots. Brown in order to make a roux, stirring constantly.
3. Add some of the cooking liquid from the soup to thin the roux out and then pour it into the soup. Bring to a gentle boil and remove from heat.
4. Add the tarragon vinegar before serving. Then garnish with chopped chives and sour cream.
*For a lighter version add low-fat sour cream or yoghurt
*To thicken the soup, mash 1 or 2 potatoes up with a fork before adding the vinegar and sour cream.
