The water absorption of flour varies, so you have to control it when you add water or milk. After the bread is colored, it should be covered with tin foil to prevent the baked color from overheating. It is best to keep the soup in the refrigerator overnight, if you make too much, you can also put it in the refrigerator, as long as it doesn't turn gray, you can use it. Pay attention to the temperature when making soup and heat it over water, otherwise the batter will become overcooked and turn into a dough. The transparent paste should be left out of the water and let cool. It is best to put it in the refrigerator overnight before using it.