Russet potatoes, halved • white vinegar • salt (I prefer kosher) • large eggs • a medium onion, minced (about 1 cup) • medium carrots, minced (about 3/4 cup) • large celery ribs, minced (about 3/4 cup) • baby sweet pickles, minced (1 to 1.25 cups) • brine from the pickles • mayonnaise • mustard • black pepper