In a large pot, cover the potatoes with water and add a pinch of salt. Bring to a boil and cook for 10-15 minutes, or until the potatoes are fork-tender. Drain and let cool slightly.
In a large bowl, whisk together the mayonnaise, Dijon mustard, apple cider vinegar, garlic powder, onion powder, salt, and pepper until smooth.
Add the cooled potatoes, celery, red onion, and parsley to the bowl. Gently fold the ingredients together until the potatoes are well coated with the dressing.
Stir in the chopped hard-boiled eggs, being careful not to break them up too much.
Cover the salad and refrigerate for at least 1 hour to allow the flavors to meld. Serve chilled.