01 - Bring a large pot of salted water to a boil. Add elbow macaroni and cook according to package directions until al dente. Drain and rinse under cold water to stop the cooking process.
02 - In a large mixing bowl, combine cooled macaroni, celery, red bell pepper, red onion, shredded carrots, and thawed peas. Toss gently to distribute the vegetables evenly.
03 - In a small bowl, whisk together mayonnaise, sour cream, Dijon mustard, apple cider vinegar, sugar, salt, and black pepper until the mixture is smooth and well combined.
04 - Pour the prepared dressing over the macaroni and vegetable mixture. Stir gently to ensure all ingredients are evenly coated.
05 - If desired, fold in fresh parsley and chopped hard-boiled eggs until combined.
06 - Cover the bowl and refrigerate for at least 1 hour before serving to allow the flavors to meld.
07 - Stir salad gently just before serving. Adjust seasoning to taste if needed.