-
Peel and cut potatoes into pieces.
-
Boil in salted water with a pinch of sugar until tender.
-
Let cool completely and place in a bowl.
-
Whisk mayo, vinegar, juice, mustard, and zest.
-
Season to taste with salt and pepper.
-
Toss the dressing with the potatoes.
-
Mix in the onion, then the parsley.
-
Refrigerate for at least 1 hour.
-
Taste and adjust the seasoning if necessary before serving.