Mix Whisky in the Jar Rub with a little apple juice to form a thin paste. Brush the pork belly slices with the paste and marinate overnight. Preheat your grill or smoker to about 120°C and place the pork belly slices over indirect heat. Feel free to add a bit of smoke. After 20–30 minutes, increase the temperature to around 180°C and continue cooking the pork belly until it reaches your desired level of crispiness. If you like, glaze with a bit of BBQ sauce shortly before serving and let it caramelize briefly.