Bring a large pot of salted water to a boil. Add the diced potatoes and cook for 10-12 minutes, or until fork-tender.
Drain and let them cool slightly.
While the potatoes are boiling, place the eggs in a saucepan and cover with water.
Bring to a boil, then reduce heat and let simmer for 10 minutes.
Transfer to an ice bath, let them cool, then peel and chop.
In a small bowl, whisk together mayonnaise, mustard, apple cider vinegar, sugar, paprika, salt, and black pepper until smooth and well combined.
In a large mixing bowl, combine the cooked potatoes, chopped eggs, red onion, celery, and pickles.
Pour the dressing over the mixture and gently toss until everything is well coated.
Cover and refrigerate for at least one hour to allow the flavors to meld.
Before serving, sprinkle with extra paprika and fresh parsley for garnish.