Usually 1 to 1 and a half hours is enough.

1. Wash and drain the water and put it in a pot with cold water. Boil until it boils and foams, then turn off the heat. Pour out the water in the pot and wash it with warm water.

2. After washing the pot, refill the water, put in the washed pork wishbone, add two or three slices of ginger, a green onion knot and an appropriate amount of cooking wine. Add enough water at one time, higher than the pork. Bone 4 to 5 cm, because the water will evaporate and become less during the cooking process.

3. Bring to a boil over high heat, then reduce to medium to low heat to maintain a slight boil and cook. Skim off any foam if there is any foam.