Bring a large pot of water to a boil, add 1 tablespoon salt, and cook the elbow macaroni according to package directions until just al dente.

Drain the macaroni in a colander, rinse under cold water until completely cool, and let it drain very well.

In a small mixing bowl, whisk together the mayonnaise, yellow mustard, apple cider vinegar, granulated sugar, kosher salt, black pepper, and paprika until smooth.

In a large mixing bowl, combine the cooled macaroni, celery, red bell pepper, red onion, dill pickles, and chopped hard-boiled eggs if using.

Pour the dressing over the macaroni mixture and gently fold everything together with a rubber spatula until evenly coated.

Taste and adjust seasoning with additional salt, pepper, or sugar if desired.

Cover the bowl and refrigerate the salad for at least 1 hour to allow the flavors to meld and the dressing to thicken slightly.

Just before serving, stir the salad again, sprinkle with fresh parsley if using, and serve chilled.