Finely chop cabbage and Chinese cabbage.

Sprinkle salt on the chopped cabbage and Chinese cabbage and set aside.

Squeeze out excess water from the cabbage mixture.

Chop green onion, garlic chives, and onion.

Mix the chopped vegetables with katakuriko.

Stir the vegetable mixture well.

In a separate bowl, combine pork mince, grated garlic, and chopped ginger.

Add the vegetable mixture to the pork mixture.

Add sake, oyster sauce, sesame oil, and pepper to the pork and vegetable mixture.

Stir the filling well.

Wrap the filling with gyoza skins, pressing in the middle first and making 3 pleats on each side.

Make gyoza in bulk and freeze half, ensuring they don't stick together.

After freezing, store the gyoza in a well-sealed bag.

Heat oil in a frying pan.

Pan-fry the gyoza until the bottoms are golden-brown.

Add flour to water for steaming to create 'wings'.

Dissolve one tablespoon of flour in 100 ml of water.

Pour the flour-water mixture into the frying pan.

Cover the pan with a lid and steam for about five minutes.

Uncover and evaporate the excess water to make the gyoza crispy.

This takes about two to three minutes.