1 medium eggplant, cut into 12 rounds
2 medium-large zucchini, sliced medium thick on the diagonal
1/4 cup extra-virgin olive oil, divided
Salt and ground black pepper
1 large tomato, cut into 6 slices and lightly salted
1 ball fresh mozzarella (8 ounces) cut into 6 slices (you will only need about 6 ounces)
Small handful basil leaves
2 teaspoons balsamic vinegar
Heat a gas grill igniting all burners on high for at least 10 minutes or build a hot charcoal fire. Clean grate with a wire brush and then lubricate with an oil-soaked rag. Toss eggplant and zucchini slices with 3 tablespoons of the olive oil and a sprinkling of salt and pepper.
Place eggplant and zucchini on hot grate and grill, covered until spotty brown on one side, about 5 minutes. Turn vegetables and continue to grill, covered, until vegetables are spotty brown on remaining side, 4 to 5 minutes longer.
As soon as vegetables come off the grill, assemble napoleons in the following order: 1 slice eggplant, 2 to 3 slices of zucchini, 1 slice mozzarella, a few basil leaves, a tomato slice, another eggplant slice and a few more zucchini slices. Lightly drizzle napoleons with remaining tablespoon of olive oil and the balsamic vinegar. Serve.