Exercise:
1. Wash the spareribs, boil them in boiling water for one minute, remove the blood foam and wash them.
2. Put the ribs in cold water, add some ginger, bring to a boil over high fire, skim off the floating foam, add a proper amount of cooking wine, salt and a drop of white vinegar, and simmer over low heat until the soup is milky white.
3. Add yam, bring to a boil, and turn to low heat until yam becomes crisp.
Tips:
1 Note that yam will change color soon, so be sure to soak it in water in advance, or cut it and put it in the pot immediately.
Put a little vinegar in the stew, and the meat will rot quickly.