Boil potatoes until cooked all the way through. Meanwhile, move on to step 2 to make the dressing.
Place the egg yolks into the bowl you’ll use to make the dressing. I used my KitchenAid stand mixer with the wire whip attachment, but you can also use a whisk. Mash the egg yolks using the whisk or stand mixer.
Add the remaining dressing ingredients and whip until well-combined. Taste and add salt if desired. Set aside in the refrigerator until ready to use.
Cool the potatoes until they’re comfortable enough to handle, then peel.
Transfer the peeled potatoes to the refrigerator. Dice the potatoes once they're fully cooled.
In a large bowl, combine the potatoes, celery, onion, and pimentos. Add the dressing and stir with a spatula until the dressing covers everything evenly.
Dice the egg whites, add to the potato salad, and stir to combine. (I add the eggs last so they don’t get broken up when combining everything else.) Refrigerate until serving.