Yukon Gold spuds.. boiled with skin.
(thats the most important part–Yukon Golds)
EEEK–Miracle Whip (Mayo if you really hate MW)
salt
pepper
(I salt and pepper the spuds after peeling them and cutting them before dumping them into the bowl)
sweet relish
shredded carrots (on the hand grater)
small jar of pimentos (very well drained)
half to 1/4 green bell pepper finely diced (depending on size)
diced celery
diced white onion
dash of yellow mustard
(mom used to do the hard boiled egg thing, but I dont like egg yolks)

Pretty basic, but everyone seems to love it.