1Cook and drain pasta shells as directed on package. Rinse with cold water; drain.
2While pasta is cooking, in medium bowl, mix all vinaigrette ingredients just until blended. Set aside.
3In another medium bowl, mix mayonnaise, 2 tablespoons basil and 1/4 teaspoon salt. Stir in tuna, carrot, zucchini and onion until evenly mixed. Fill each pasta shell with 1 rounded tablespoon tuna mixture.
4Line serving platter with lettuce leaves. Arrange shells on lettuce. Serve with vinaigrette.