Picnic-Worthy Potato Salad

When I was growing up, the ingredients for the best potato salad were the subject of ongoing debate. Eggs or no eggs? Sweet pickle relish or dill? White or green onions? Mustard and mayo? Firm cooked potatoes or mashed to a purée? Over the years I’ve tried them all and come up with this version, which gets my vote as the absolute best. I love this potato salad at room temperature, but it can be refrigerated to let the flavors meld for several hours or up to overnight before serving.