Peel potatoes, if desired, and cut into pieces. Cook in boiling water to cover in a Dutch oven 30 minutes or until tender; drain and cool.
Chop egg whites.
Mash yolks with a fork in a large bowl; stir in mayonnaise and next 4 ingredients until blended. Add potato and chopped egg whites, tossing gently to coat. Cover and chill 1 hour. Garnish, if desired.