Heat the grill to medium-high and line a baking sheet with foil. Lay the chicken breasts upside-down on the foil, brush with 1 tbsp of barbecue sauce, then grill for 5 mins. Turn the chicken breasts over, add the bacon rashers to the tray, then return to the grill for a further 5 mins.
Drizzle the chicken with the remaining barbecue sauce, sprinkle with cheese, then place back under the grill for 2-3 mins until the chicken is cooked through, the cheese is bubbling and golden and the bacon is crispy. Top the chicken with the bacon to serve.
If you don’t like barbecue sauce, spread the chicken with tomato relish or salsa instead.