Cook Potato Skins according to package directions.
Mash together eggs, mayonnaise, mustard, salt and pepper. Stir in celery, red onion, and parsley.
On work surface, place 8 Potato Skins, skin side down; top each with 2 tbsp egg salad. Repeat layers. Sprinkle with paprika (if using).
Tip: For a spicier version, add some prepared horseradish to egg salad.