Perfect for that summer-to-fall transition period, sweet potatoes give classic potato salad a fresh spin.
In a large saucepan, cover the potatoes with 1 inch of cold water; salt generously. Bring to a boil over medium-high heat. Reduce heat to medium. Simmer until the potatoes are just tender, about 10 minutes. Drain, then transfer to a large bowl. Sprinkle with the vinegar. Using a silicone spatula, gently toss the potatoes and vinegar.
In a medium bowl, mix the celery, onion, mayonnaise, relish, chives, parsley, and mustard; season with salt and pepper. Gently fold into the potatoes. Cover and chill until the flavors meld, about 30 minutes.