Dry pork shank thoroughly with paper towel to remove moisture (to avoid oil splatter during frying).
Heat 2 tablespoons oil in a wok or a large dutch oven over medium high heat until warm. Add pork shank and let it roast for 2 to 3 minutes. Flip and cook the other side for another 2 to 3 minutes. Keep flipping and cooking, until the the entire surface is golden brown. Add 6 cups water (or more) to cover the pork shank.
Add Sichuan peppercorns and coriander seeds to a mesh tea strainer or infuser. (See footnote 1)
Add the tea strainer, garlic, green onion, ginger, cinnamon stick, star anise, and five-spice powder to the pot. Mix well.
Continue cooking to bring to a boil. Skim the foam from the surface until the broth is clear.
Cover and turn to low heat. Simmer for 40 minutes. The broth should continue boiling throughout the process.
Add light soy sauce, dark soy sauce, Golden Mountain Sauce and palm sugar. Mix well.
Cover and bring to a boil over medium high heat. Keep covered and simmer for 1 hour.
(Optional) Heat the remaining 1 tablespoon oil in a skillet over medium high heat until warm. Spread chicken thighs. Allow to cook without moving for 2 to 3 minutes, until the bottom side turns golden. Flip and cook the other side until golden. Transfer to the pot with the braising pork shank.
Add the black beans, along with all the liquid, into the pot with the pork. (See footnote 2)
Cover and turn bring to a boil over medium high heat. Keep covered and simmer for 1 hour, until the pork turns tender. If the broth runs low before the pork becomes tender, add warm water to cover pork.
If the broth is still thin, turn to medium high heat and cook uncovered until the sauce thickens. The starch from the black beans will help the sauce thicken, so there should be quite a lot of sauce (about half) left when it’s finished cooking.
Serve the meat, beans, and sauce over steamed rice.
Store the leftovers in an airtight container in the fridge for up to a week, or in the freezer for up to 2 months.
If you have leftover sauce, do not throw them away! Add them to a bowl of noodles, so you can create a rich and hearty noodle soup effortless (see recipe here).