Place the cubed potatoes in a large pot, cover with water, and bring to a boil. Reduce the heat and simmer for about 10-15 minutes until the potatoes are fork-tender.
Drain the potatoes and let them cool slightly. Use a potato masher to mash them a few times, still leaving some chunks.
In a large mixing bowl, combine the mayonnaise, sour cream, mustard, chopped eggs, grated onion, celery, dill pickles, and pickle juice. Add the cooled potatoes, salt, and pepper. Stir gently until all ingredients are well combined.
Cover the bowl with plastic wrap and refrigerate for at least 2 hours. Before serving, adjust seasonings if needed and then sprinkle with paprika for a colorful finish.