2 pounds potatoes
1/2 cup beef or chicken stock
1/2 onion, chopped
6 tablespoons wine vinegar
6 tablespoons olive oil
1 teaspoon salt
1/2 teaspoon freshly ground pepper
1 egg yolk
Wash and scrub potatoes. boil in jackets until tender. Let cool only enough to peel and slice. pour stock over to be absorbed by potatoes. Add onion. Mix remaining ingredients. beat smoothly together. Pour over potatoes. Serve warm or chilled.
Serves 4