Put the potatoes in a saucepan and add enough water to cover. Bring to a boil. Cook, partially covered, for 25 to 30 minutes, or until fork tender.
Drain and cool. Peel and cut the potatoes into 1-inch chunks. Put the potatoes in a salad bowl. Add the eggs, salt, cayenne, black pepper, celery, green onions, and parsley. Combine the mayonnaise and mustard and add to the bowl. Toss to mix well.
Serve immediately or refrigerate and serve slightly chilled.
Yield: 4 servings