A northern food

After mixing the noodles and wrapping them in a cloth

Washing them in water

washes away the starch

leaves the protein and other water-insoluble stuff, which is commonly known as gluten

This is just the simplest way to do it

There are also a few things you can add to make the gluten fluffy and soft, etc.

It is also a good idea to add some other things to make it more fluffy and soft, so you can add some other things to make it more fluffy and soft.

^_^