procedure

 
In a food processor or using a mortar and pestle, combine garlic, cilantro stalks, lemongrass, oyster sauce, soy sauce, black peppercorns, brown sugar and salt. Blitz or pulverize until smooth.
Cut pork jowl into strips about 2 inches (4.5 cm) thick. Pour marinade over pork jowl and make sure everything is evenly coated. Cover and let marinate in the fridge overnight.
When ready to cook, take pork jowl out about 30-1 hour before cooking and allow to warm up to room temperature before grilling them on a bbq or underneath the broiler in the oven. Cook for about 5-7 minutes on each side or until jowl is firming up and the outside starts to crisp and carmelize.
When finished grilling, remove from heat and rest on a plate on a plate for about 5 minutes before cutting into them. Cut at an angle and against the grain to get the best slices.
For the dipping sauce, In a food processor or using a mortar and pestle, combine all ingredients together and blitz or pulverize until smooth. Let sit for about 10-15 minutes to ensure all ingredients marry together then serve.