2 pounds cooked potatoes
1/4 cup white-wine vinegar
1/2 cup olive or vegetable oil
1 tablespoon Dijon-style mustard
salt and pepper, to taste
1 cup chopped green onion or chives
2 tablespoons chopped fresh parsley
1 tablespoon chopped fresh tarragon
Slice the cooked potatoes while they’re still warm. Sprinkle with half the vinegar. Mix the rest of the vinegar with the oil, mustard, salt, and pepper; pour over potatoes. Toss with onion and herbs, and correct the seasonings.