Potato Salad with Fresh Corn and Basil

Name: Potato Salad with Fresh Corn and Basil
Ingredients: 2 quarts water; 2 tablespoons plus 2 1/2 teaspoons kosher salt, divided, plus more to taste; 1 medium ear fresh yellow corn, husk and silk removed; 2 1/2 pounds baby red potatoes, cut into 1-inch pieces (about 7 1/2 cups); 1 small yellow onion, finely chopped (about 1 cup); 3 tablespoons white wine vinegar; 3 medium celery stalks, finely chopped (about 1 cup); 3/4 cup mayonnaise; 3 tablespoons chopped fresh basil; 1 tablespoon chopped fresh dill, plus dill sprigs, for garnish; 1 teaspoon black pepper, plus more to taste