Granny’s Potato Salad with Pickled Onions

My favourite potato salad dates back to the fifties and I don’t think a barbecue is complete without it. Potato salad went out of fashion after being destroyed by grocery stores and bad delis that drowned it in blobs of mayonnaise. The authentic version has to be ice-cold, mixed with tangy sauce and crisp bits of celery and chopped pickle. The perfection lies in tossing the warm potatoes and onions in vinegar first, then letting them cool before mixing in the rest.