This is my mother's potato salad with a few tweaks of my own. No one in my family had ever written this recipe down, and I don't think we ever measured anything, until I made 30 lbs. for my nephew's graduation party! Chilling overnight and serving on the second day is key.
The day before serving: Boil whole white potatoes in salted water just until fork tender. Cool completely, then peel and cut into approx. 3/4” cubes. Place potatoes in very large mixing bowl or in roaster pan.
Add diced celery and onion, parsley and eggs to potatoes; stir to combine.
Combine mayo, salad dressing, sour cream, mustard and S&P in medium mixing bowl; add to potato/vegetable mixture. Stir well to coat all ingredients with dressing.
Cover and refrigerate overnight.
Day of serving: Taste. Adjust seasonings, if desired. Add extra mayo/miracle whip, or a small amount milk, if needed for good consistency.
If desired, garnish with a sprinkle of paprika or parsley, and sliced hard boiled eggs.