1. Blanch lamb bones with cold water into the pot and pour 2 tablespoons of cooking wine
2. Peel the yam and cut into pieces for later use
3. Scallion, ginger, dried chili, cinnamon, star anise and cloves. Match the seasoning according to your own taste
4. Low heat, put oil in the pot and stir fry with rock sugar until frothy
5. Add lamb bones and stir-fry, add water, green onion, ginger, chili aniseed, pepper powder, soy sauce
6. Pour into the pressure cooker and add water, the water should flow through the pressure valve of the bone cover for 20 minutes
7. Pour in the yam and simmer over medium heat for 10 minutes
