This is a little embarassing to admit, but when I've had many unexpected extra people at meal times I've made potato salad out of a large box of instant potatoes. Cut back on the liquid, stir in mayonnaise, sour cream, mustard, pickle relish, salt & pepper. A dash of onion powder and a few Bacos is also good. Serve hot. The last time I went to the trouble of cooking 'homemade' potato salad my family admitted they liked the other as well or better.