Cut the meat into 5 cm (2 inch) cubes and place in a deep pot with the spring onions, ginger, star anise, and the orange peel. Cover with water and bring to a boil, skim and then simmer for 2 hours, tightly covered over low heat. Heat the lard and fry the seasoning ingredients for 1 minute, then pour into the pot and recover. Simmer 1 hour more or until meat is very tender. Transfer meat to a serving dish and thicken the sauce with a paste of corn flour and cold water. Pour over the meat after discarding the onion, ginger, star anise and orange peel.