In a medium bowl mix all the filling ingredients together.
Prepare the chicken by placing one hand on top of the breast to keep it steady. Insert a sharp knife into the middle of the thickest section. Cut a slit roughly 5cm long. Continue to run the knife into the breast until it’s three-quarters of the way through, to create a cavity. Fill with 2 tablespoons of the filling. Thread a small bamboo skewer or toothpick through the breast to enclose the stuffing.
Once the chicken is stuffed and secured, gently lift the skin. Push a piece of prosciutto under the skin. Lightly coat the chicken with oil and season with salt and pepper on all sides. Refrigerate for 1 hour.
To prepare the Pulse for roasting over medium heat (210° to 240°C), preheat the barbecue by turning the control knob(s) to high. Preheat until the barbecue reaches at least 260°C, which will take approximately 15 to 20 minutes with the lid closed. Once the barbecue is preheated, open the lid and brush the cooking grills clean. Adjust the control knob(s) to medium for roasting over medium heat.
Cook the chicken, skin side down first, with the lid closed, for 10 minutes. Turn the chicken over, close the lid, and continue to cook until the internal temperature reaches 71°C, 10 to 15 minutes more. Remove from the barbecue. Allow to rest for 5 minutes before slicing (while the chicken is resting, the internal temperature will rise 3° to 6°C to reach 74°C).