1. Cut pork belly into 3-4 big chunks and mix with marinade ingredients. Deep-fry in hot oil until golden brown and pork skin firm up and crispy. Dish up and rinse with water. Keep aside.
2. Use a fork (or toothpick) to prick some holes on the skins to allow the pork to absorb gravy later. Cut into 1.5cm thick slices. The half-cooked pork belly enable more efficient slicing process, unlike wobble raw meat slicing.
3. Clean yam and skin. Cut yam into 1cm thick slices and deep-fry in hot oil until golden brown. Dish up and drain. Absorb excess oil with kitchen towels.
4. Arrange pork belly and yam alternately onto a steaming bowl and pour over gravy.
5. Steam pork belly and yam on high heat for 1-2 hours until yam and pork is cooked and tender (the longer the better, so as pork belly is tender enough to melt in your mouth). Serve hot with white rice.
If you're particular about aesthetics and presentation, you can invert onto a serving plate lined with lettuce with sesame oil drizzled on top. Place the serving plate over steaming bowl, then invert it quickly.