Bring a large pot of water to a boil over high heat, then add the peeled and cubed russet potatoes and boil until tender, 10-15 minutes, with a steady simmer and easy knife-tender centers.

Drain the potatoes and let them cool completely until no longer warm to the touch, about 15-20 minutes, so the salad dressing stays creamy and doesn’t thin.

In a large bowl, combine the cooled potatoes, chopped hard-boiled eggs, diced celery, finely diced onion, and sweet pickle relish and stir until evenly distributed with visible specks of egg and relish throughout.

In a separate bowl, mix mayonnaise, yellow mustard, white vinegar, sugar, salt, and pepper until smooth, thick, and glossy, with no dry sugar pockets.

Pour the dressing over the potato mixture and fold gently until the potatoes are fully coated, 1-2 minutes, and the salad looks evenly creamy rather than mashed.

Cover and refrigerate for at least 2 hours to chill and set the flavors, 2-3 hours total, until cold in the center and sliceable for serving.

Just before serving, sprinkle paprika over the top for garnish so the final bowl has a bright, traditional red-speckled finish.