1. First, blanch the pig leg bones for 3-5 minutes to remove the blood from the meat.
2. Then take out the scalded pig leg bone, rinse it with warm water for 2-3 times, and then rinse the blood foam and impurities again.
3. Fill the casserole with water again, add the pork leg bones, salt and ginger into the pot and bring to a boil.
4. Then cover and cook for 3-4 hours. If the soup in the middle evaporates a lot, you can add some boiling water.
5. At this time, filter the cooked broth with a strainer and store it in the refrigerator.