Hold the pineapple firmly by its leaves (careful of the spikes) and use a sharp knife to cut the skin off. Cut horizontally into 1cm slices and set aside - keep the leaves!
Whisk together the brown sugar with all the spices. Use this rub to thoroughly coat the chicken breasts.
Use a sharpened dowling stick and impale the bottom slice of the pineapple to make a sturdy skewer. Layer the kebab with three chicken pieces followed by one slice of pineapple, finishing with the pineapple leaves on top.
Roast for around an hour until nearly cooked through - the pineapple will tenderise the chicken and keep it extra moist.
Meanwhile heat all the ingredients for the BBQ sauce in a wide saucepan. Stir until the sugar has dissolved and bubble down until it's nice and thick.
Brush the kebab with half the sauce and place back in the oven until cooked through.
Slice off slithers of the kebab and serve in cheese slathered toasted subs with crispy bacon and the remaining half of the BBQ sauce.