4+ hours in advance: cook potatoes and hard boil eggs
In Instant Pot:
Spray bottom of Instant Pot and add cut potatoes, then place uncooked, in shell eggs directly on top of them potatoes. Pressure cook on high for 5 minutes, and use quick release (immediately rotate the vent to release) when done. Carefully, to avoid burns, move eggs to ice water for 5 minutes, then peel and refrigerate; drain potatoes, then move to large bowl and refrigerate.
On stove top:
For potatoes: start a large pot of water boiling, add potatoes and cook until tender, about 6-10 minutes depending on variety and size cut. Drain, move to a large bowl and refrigerate until cool.
For eggs: use preferred method of hard boiling, or: place uncracked eggs in pot and fill with cold water to completely submerge eggs. Place on burner and turn to high, set time for 18 minutes - boiling time should be about 6-8 minutes depending on stove burner and altitude. When timer finishes, move eggs to ice water for 5 minutes, then peel and refrigerate.
About an hour before serving
Mix together all the dressing ingredients in a small bowl, then cover and refrigerate for an hour to let flavors combine.
Just before serving
Chop the eggs, add to potatoes, and pour the dressing on and mix carefully to avoid making mashed potatoes.