Preparation:
Barbecue the chicken breasts for 8 minutes on one side on high heat, and 5 minutes on the second side on medium heat with the barbecue lid closed.
Mix the olives, capers and Parmesan in a bowl.
Turn off the heat under the chicken breasts, leaving the other side of the barbecue on medium high.
Top the chicken breasts with the tomato slices and the caper-olive mixture.
Close the lid and cook on the barbecue for a further 5-8 minutes with the lid closed (indirect heat). Sprinkle with fresh basil.