1. Cook the Macaroni: Bring a large pot of salted water to a rolling boil. Add the elbow macaroni and cook according to package directions until al dente, usually 8-10 minutes. The pasta should be tender but still have a slight bite.

2. Rinse and Cool the Pasta: Once cooked, drain the macaroni thoroughly in a colander. Rinse it under cold water until it’s completely cool. This stops the cooking process and prevents the pasta from clumping together. Ensure it’s well-drained before proceeding.

3. Prepare the Dressing: While the pasta cools, in a large mixing bowl, whisk together the mayonnaise, apple cider vinegar, granulated sugar, Dijon mustard, salt, and black pepper until the mixture is smooth and well combined. Taste and adjust seasonings if necessary; you might want a little more sugar or a pinch more salt.

4. Chop the Vegetables and Eggs: Finely dice the celery stalk, red onion, and green bell pepper. If using, chop the hard-boiled eggs into small pieces. Uniformly diced vegetables ensure every bite has a good mix of textures and flavors.

5. Combine All Ingredients: Add the cooled and drained macaroni, diced celery, red onion, green bell pepper, and chopped hard-boiled eggs (if using) to the bowl with the dressing.

6. Mix Thoroughly: Using a large spoon or spatula, gently fold all the ingredients together until the macaroni and vegetables are evenly coated with the creamy dressing. Make sure no dry spots remain.

7. Chill Before Serving: Cover the bowl tightly with plastic wrap and refrigerate for at least 2 hours, or preferably longer, to allow the flavors to fully meld and the salad to chill completely.

8. Garnish and Serve: Before serving, give the salad another gentle stir. Garnish with fresh chopped parsley, if desired, for a pop of color and freshness.