Practice: 1. Wash the oxtail, blanch it with hot water to remove the oil slick, and take it out for later use.
2. Wash onions, potatoes and tomatoes, peel them and cut them into 1cm cubes.
3. Put oxtail ginger slices into clear water, bring to a boil over high fire, add chopped onions, potatoes and tomatoes, and stew for 2 hours.
4. Finally, you can put some tomato sauce and add salt.