Place the cubed potatoes in a large pot and cover with cold water by about an inch. Add 1 teaspoon of salt. Bring to a boil over medium-high heat, then reduce heat and simmer for 10-15 minutes, or until potatoes are fork-tender but not mushy. Drain thoroughly and set aside to cool completely, about 10-15 minutes.

While potatoes are cooking, place eggs in a medium pot and cover with cold water. Bring to a rolling boil, then immediately remove from heat, cover, and let stand for 10-12 minutes. Drain the hot water and transfer eggs to an ice bath for 5 minutes to stop cooking and aid in peeling. Peel the eggs and pat dry.

Carefully slice each hard-boiled egg in half lengthwise. Scoop out the yolks into a small mixing bowl. Place the whites in a separate bowl and finely chop them.

Mash the egg yolks with a fork until smooth. Add the mayonnaise, Dijon mustard, yellow mustard, apple cider vinegar, relish, 1/2 tsp salt, and 1/4 tsp black pepper to the mashed yolks. Mix well until completely combined and creamy.

In a large mixing bowl, combine the cooled, diced potatoes, chopped egg whites, finely diced celery, and minced red onion.

Pour the deviled egg dressing over the potato mixture. Gently fold everything together until all ingredients are evenly coated. Be careful not to mash the potatoes too much.

Taste and adjust seasonings as needed, adding more salt, pepper, or mustard if desired.

Cover the bowl tightly with plastic wrap and refrigerate for at least 1 hour, or preferably 4 hours, to allow the flavors to meld. This step is crucial for the best taste.

Before serving, give the potato salad another gentle stir. Garnish generously with smoked paprika and fresh chopped chives or parsley.