Slice each eggplant crosswise into 12 circles. Toss with 3 tbsp (45 mL) of the oil, salt and pep-per. Place on greased grill over medium high heat and grill for about 10 minutes, turning once until golden and tender. Remove to platter and set aside.
Slice halloumi crosswise into 12 slices. Toss gently with remaining oil and place on well greased grill about 3 minutes, turning once or until golden and warmed through.
Place half of the eggplant slices onto 6 plates, spread with some of the tapenade. Top with basil leaf. Place tomato slice and halloumi on top. Spread with remaining tapenade and top with re-maining eggplant slices.
Chop remaining basil and sprinkle over top. Drizzle with balsamic to serve, if using.