Begin by bringing a large pot of salted water to a rolling boil over high heat. Add the dried macaroni and cook for 10 to 12 minutes, or until al dente. For a softer texture, boil for 2 extra minutes. Once cooked, drain and transfer the macaroni to a colander, allowing it to cool.

Once the macaroni is drained, rinse it under cold running water for about 30 seconds. Allow the pasta to drain thoroughly, then set it aside while you prepare the dressing.

In a medium bowl, whisk together the mayonnaise, apple cider vinegar, sugar, sweet relish, and Dijon mustard until smooth and creamy. Season with salt and black pepper to taste.

In a large mixing bowl, combine the rinsed macaroni, diced red bell pepper, chopped celery, diced red onion, and chopped hard-boiled eggs. Pour the prepared dressing over this mixture.

Gently toss all ingredients together until evenly coated. Ensure noodles and vegetables are thoroughly mixed.

Taste the salad and adjust seasoning with more salt and pepper if necessary.

Cover the bowl with plastic wrap or transfer to an airtight container, then refrigerate for at least one hour before serving.