Cut zucchini length-ways into thick slices or half if zucchini are small. Mix oil and garlic together then brush over both sides of the zucchini.
Barbecue or char-grill until tender. Transfer to a tray. Cool 10 minutes.
Remove 1 cup basil leaves from the bunch. Scatter over the zucchini and season. Drizzle with extra virgin olive oil and squeeze over the juice from ½ lemon. Pile onto serving plates. Finely grate over parmesan cheese and serve with remaining lemon.