Place potato chunks in a large pot and cover with cold water by 1 inch. Add 1 tablespoon salt to the water.
Bring to a boil over high heat, then reduce to a simmer. Cook until potatoes are tender when pierced with a fork, about 12-15 minutes.
While potatoes cook, cook bacon in a skillet over medium heat until crispy. Transfer to paper towels to drain, then crumble when cool.
Drain potatoes in a colander and spread them out on a baking sheet to cool completely, about 1 hour.
In a large bowl, whisk together mayonnaise, sour cream, Dijon mustard, apple cider vinegar, sugar, salt, and pepper until smooth.
Add cooled potatoes to the dressing along with celery, red onion, dill, and crumbled bacon. Gently fold everything together until evenly coated.
If using hard-boiled eggs, fold them in gently at the end to avoid breaking them up too much.
Cover and refrigerate for at least 30 minutes before serving to allow flavors to meld.
