Preheat grill to high.
Heat oil in a large ovenproof frying pan over medium-high heat. Cook chicken for 4 minutes or until browned. Turn. Continue to cook chicken, whilst topping with barbecue sauce, ham and pineapple slices. Pour reserved juice into the pan.
When chicken is just cooked through, top it with cheese and place it under the grill. Cook for 2 minutes or until cheese is golden and melted. Serve chicken with pan juices.
