While potatoes simmer, place eggs in a small pot and cover with cold water. Bring to a gentle boil, then remove from heat and let sit covered for 10 minutes for firm yolks. Transfer eggs to an ice bath for 5 minutes, peel, and chop.

Drain potatoes, return to the warm pot off the heat for 1 minute to evaporate excess moisture. Cool slightly until warm, then transfer to a mixing bowl. Warm potatoes accept dressing without becoming gluey.

In a separate bowl combine mayonnaise, sour cream, Dijon mustard, white wine vinegar, salt, and pepper. Whisk until smooth and glossy; note the bright, tangy aroma of the dressing.

Add chopped celery, red onion, dill pickle relish, and most of the parsley to the warm potatoes. Gently fold in the dressing until potatoes are coated but still in distinct pieces, keeping texture contrast alive.

Fold in chopped hard boiled eggs carefully to avoid breaking yolks into paste. Taste and adjust salt, pepper, or vinegar. The mixture should feel creamy with bursts of acidity and crunch.

Chill the salad for at least 1 hour to let flavors marry. Serve cold or slightly chilled, garnished with remaining parsley and a sprinkle of paprika if you like a visual pop.