In a bowl add the brown sugar, kosher salt and apple cider. Stir to dissolve.
Add 2 cups of cold water to the bowl. Add two tablespoons of olive oil, balsamic vinegar, pepper, rosemary branches and bay leaves.
Place the pork chops into a large sealable plastic bag. Place this plastic bag into another of equal size to offer extra safety. The plastic bags can be standing in a large pot to make it more secure. Pour the brine overtop of the chops and seal the plastic bags. Place in the refrigerator to rest for a minimum of 4 hours up to overnight.
After the required time has passed, remove the pork chops from the brine and place on a large tray. Pat them dry with paper towel and dispose of the brine. The pork chops have to come to room temperature before grilling.
Preheat the barbecue to 500°F/250°C with heat on one side of the grill and no heat on the other.
Lightly brush both sides of the pork chops with olive oil and season with salt and pepper. Sear the pork chops over direct high heat for 6 minutes, turning once halfway through cooking time. Lower the temperature to 300°F/150°C and move the chops to the cool side of the grill.
Continue to cook the pork chops over indirect medium heat for about 8 minutes per side with the lid closed.
Once the juices run clear, take the pork chops off the grill and tent with aluminium foil. Allow to rest before serving.