2. Sour soup, a traditional Manchu delicacy, is popular in eastern Liaoning, southeastern Jilin and Heilongjiang.

3. Sour soup is a coarse noodle-like staple food fermented by corn mill. It tastes delicate and smooth, and coarse grains are nutritious and healthy. It is a green and nutritious food.

4, the specific method is: first use boiling water to iron the noodles, after the soup is boiled, roll the noodles from a thin iron sheet into a small iron tube and squeeze them into the pot, squeeze them and get one. After all the noodles are squeezed, add some tender cabbage or spinach, add salt and seasoning and cook.