Peel and quarter potatoes; cook in a Dutch oven in boiling salted
water to cover until done. Drain and cool.
Cube potatoes; add eggs, pickles, celery seeds, mustard, salt,
pepper, and dressing. Stir gently. Refrigerate 24 hours. Garnish
with parsley sprigs before serving, if desired.
Dressing:
Place egg yolks and sugar in a small saucepan; gradually add
vinegar, mixing well. Add butter and place over medium heat,
stirring constantly, until mixture comes to a boil. Remove from
heat, and chill. Add mayonnaise, and mix well.
