This is always a hit at family and friend gatherings. My son wanted me to make it for Thanksgiving. Since it has onion, I don't eat it myself, but everyone says it is awesome. This makes a large batch. The dressing can be increased or decreased, depending on how moist you like your salad.
Boil whole potatoes until fork tender. Remove from water and allow to cool. Meanwhile, chop the onion, celery and eggs. Set aside. When potatoes are cool enough to handle, peel. Cut into bite sized pieces. Add onion, celery, and egg. In separate bowl combine Miracle whip and mustard. Pour over potato mixture. Stir to evenly distribute dressing. Refrigerate and serve cold.