Eggplant Caprese with Grilled Tomato and Basil Vinaigrette

Name: Eggplant Caprese with Grilled Tomato and Basil Vinaigrette
Ingredients: 1 (1-pound) globe eggplant, trimmed, cut crosswise into 1/2-inch-thick rounds; Olive oil (for grilling); 1 large plum tomato (about 4 ounces); 1/3 cup chopped fresh basil plus sprigs for garnish; 1 tablespoon white wine vinegar; 1/4 cup olive oil; 2 (7- to 8-ounce) balls fresh or buffalo mozzarella cheese, drained, thinly sliced; 2 pounds (about 4 large) heirloom tomatoes (preferably assorted colors), thinly sliced