2Place bones, trotters, and back fat in a large pot with 6000g water. Bring to a boil, then drain and rinse bones.
3Return bones, trotters, and back fat to the pot with 6000g fresh water. Add pork belly, pork fat, garlic, ginger, scallions (white parts), and onion. Simmer for 8 hours, skimming impurities.