01 - Place cubed potatoes in a large pot and cover with cold salted water. Bring to a boil over medium-high heat, then reduce heat and simmer for 10-12 minutes until fork-tender.
02 - Drain potatoes thoroughly and spread on a baking sheet to cool for 10 minutes.
03 - Whisk together mayonnaise, sour cream, Dijon mustard, apple cider vinegar, salt, and pepper in a large mixing bowl until smooth.
04 - Add cooled potatoes, celery, red onion, parsley, and chives to the dressing. Gently toss to coat all ingredients evenly.
05 - Fold in chopped hard-boiled eggs. Taste and adjust seasoning as needed.
06 - Cover and refrigerate for at least 1 hour before serving to allow flavors to meld. Garnish with additional herbs if desired.