Creamy Vegan Fingerling Potato Salad Recipe

Name: Creamy Vegan Fingerling Potato Salad Recipe
Ingredients: 1 1/2 pounds fingerling potatoes (such as La Ratte or Russian Banana), cut into 1/2-inch disks; 1/2 pound yukon gold potatoes (about 1 large), peeled, quartered lengthwise, and cut into 1/2-inch slices; Kosher salt; 2 1/2 tablespoons white wine vinegar, divided; 1 tablespoon whole grain mustard; 1 tablespoon pickle relish; 1 tablespoon sugar, plus more as desired; 2 small shallots, one minced (about 1/4 cup), one thinly sliced (about 1/4 cup); 1/4 cup extra-virgin olive oil, divided; 1 tablespoon capers, rinsed, drained, and roughly chopped; 2 stalks celery, finely diced; 1/4 cup roughly chopped fresh parsley leaves