Place potato chunks in a large pot and cover with cold water by about an inch. Bring to a boil over high heat, then reduce to a simmer and cook for 12-15 minutes until potatoes are tender but not falling apart.

While potatoes cook, place eggs in a small saucepan and cover with water. Bring to a boil, then cover and remove from heat. Let sit for 10 minutes before transferring to ice water to cool.

Drain cooked potatoes and spread them on a baking sheet to cool slightly for about 10 minutes—they should still be warm but not hot.

Peel and chop the hard-boiled eggs into bite-sized pieces.

In a large mixing bowl, whisk together mayonnaise, sour cream, Dijon mustard, apple cider vinegar, salt, pepper, and garlic powder until smooth.

Add the warm potatoes to the dressing and gently fold until all pieces are coated.

Stir in chopped eggs, red onion, celery, and fresh dill until evenly distributed.

Cover and refrigerate for at least 1 hour before serving to allow flavors to meld.