Bring a large pot of water to a rolling boil
Add a large pinch of salt and 3 pounds of potatoes into the boiling water
Boil potatoes for 20-25 minutes
Drain potatoes in a strainer and then cover the strainer with a kitchen towel and allow the potatoes to sit covered (in the strainer) for 20-25 minutes
Combine 3/4 cup of mayonnaise, 1/4 cup of sour cream (or buttermilk) and 1/8 cup of a grainy dijon mustard in a large bowl
Add 1 tablespoon of onion powder, 2 teaspoons of garlic powder and 1 teaspoon of celery salt and whisk to combine
Add 3 peeled hard boiled eggs (finely chopped or mashed) and mix to combine
Once the potatoes are cool enough to touch, carefully peel them (optional) and cut them into large cubes
Add the cubed potatoes into the dressing and toss until fully incorporated
Add 1/2 cup of finely chopped red onion, 1/3 cup of finely chopped fresh dill, 2 celery ribs that have been finely chopped and 2 spring onions that have been thin sliced
Gently mix until all of the ingredients are fully incorporated
Cover and chill in the refrigerator for several hours or overnight
Store leftovers in an airtight container in the refrigerator