Begin by combining finely chopped cabbage and salt in a bowl. Toss them together. And allow them to sit for five minutes to extract the cabbage's moisture. Afterwards, extract the moisture from the cabbage. Do it by squeezing it and discarding the liquid.
In a large mixing bowl, combine ingredients. Such as squeezed cabbage, pork mince, soy sauce, sake, sesame oil, ginger juice, salt, and pepper. Mix everything together.
Next, place a tablespoon of the filling in the centre of each gyoza wrapper. And seal the edges by pinching them together. Repeat until all the filling completes.
Heat some oil in a frying pan over medium heat, arrange the gyoza in a circle, and let the bottoms brown slightly. In a separate bowl, mix together potato starch, flour, and water. Once the gyoza bottoms have slightly browned, pour the starch mixture into the pan.
Cover the pan with a lid and steam the gyoza over low heat for approximately five minutes. Take off the lid and allow the water to evaporate so that the starch mixture can form a crispy lattice. You can increase the heat to medium, but be cautious not to burn the gyoza bottoms.
Lastly, turn off the heat and serve the gyoza with the bottom facing up on a plate.