1-Cook macaroni according to package directions, aiming for 12 to 14 minutes for a slightly more than al dente texture.

2-Rinse the cooked macaroni thoroughly under cold water until completely cool, then drain well and place in a large bowl.

3-Sprinkle the apple cider vinegar over the cooled macaroni, add the shredded carrots and optional shredded onion, and toss together well.

4-Refrigerate the macaroni mixture for 15 minutes or until fully cooled.

5-In a separate bowl, whisk together the mayonnaise, milk, and sugar until smooth.

6-Fold the mayonnaise mixture into the cooled macaroni mixture until the noodles are evenly coated.

7-Season with salt and pepper to taste.

8-Cover the bowl and refrigerate for at least 4 hours, ideally overnight.

9-Before serving, gently stir the salad; if it seems dry, add 1 to 2 tablespoons of milk and fold gently to avoid breaking the noodles.