A creamy potato salad with chopped boiled egg, plenty of salt and pepper, and unabashed use of mayonnaise in it comforts us like little else. You might decide that’s all we need heading into summer. On the other hand, a bunch of other vegetables embedded in potato salad provides a colorful side dish that gives us a wholesome serving of vegetables, and stands in for two or three other side dishes. Start with boiled potatoes drained and liberally sprinkled while they cool with rice, cider, or white wine vinegar to brighten the salad’s flavor.