Flour, cornflour, and salt should then be added to the prepared medium bowl. Add water a little at a time, mixing with a spatula as you go. (For example, add the first third of the water and stir the flour thoroughly. Mix in a further third of the water.) Keep doing this up until a rough dough develops.
Knead the dough for about 5 minutes, or until it is smooth, elastic, and sticks together tightly. It ought to be sealed tightly in a plastic bag. The dough should be refrigerated for two hours.
The soup stock should be started boiling in a medium-sized saucepan over medium-high heat. Add the onion and potato. for around ten minutes.
Place a small dish of water next to the burner while the soup is simmering. To easily stretch and pull the dough, use this to wet your fingers, primarily your thumb and index finger. Making the dough flakes thin also aids in preventing doughy bites.
Add the salt, soy sauce, minced garlic, carrots, zucchini, and mushrooms after lowering the heat to medium. Cook the vegetables for 5 minutes, stirring periodically, or until they are softened but not overcooked. Pieces of cooked dough should appear transparent and to be floating in the broth. Add the green onions as a garnish.