1. Mix salt and alkali flour with a small amount of warm water, add flour, then add the remaining water, mix while adding water, knead into dough with smooth and tough surface, cover with wet towel for 20 minutes.
2. Divide the dough into 8 small parts on average, rub the dough into long strips, brush the surface with oil and put it in the fresh-keeping box for more than 2 hours.
3. Add water to the pot and heat it with high fire. Because my "pulling" effort is not so good, I can only roll the small strips into thin and wider patches, hold both ends with my hands, and gently beat the patches on the operating platform to stretch them into longer and thinner long patches.
4. Boil the stretched dough in the boiling water pot, stir evenly with chopsticks, boil until the dough is boiled again, add some cold water, cook for about 4 minutes on a low heat, finally add the rape and soybean sprouts together for another half a minute, turn off the heat, remove the noodles and vegetables and put them into a larger bowl.
5. Pour soy sauce and vinegar into the bowl, sprinkle scallion, ginger and chili on the surface.
6. Heat the pot, add the rapeseed oil, turn off the heat after the oil is heated, and pour it on the chili powder in the bowl.