Boil, peel and cube 1 pound potatoes. Toss with 1 tablespoon cider vinegar and 1/2 teaspoon salt. Mix 1/4 cup each mayonnaise and sour cream and 2 tablespoons each horseradish and chopped chives. Toss with the potatoes, 1 chopped celery stalk, and salt and pepper.
Photograph by Antonis Achilleos