Finely chop the napa cabbage and put it in a medium bowl. Sprinkle salt and rub the napa cabbage with your hands. Set aside for 10 minutes.
Gather all the ingredients to make the gyoza filling.
In a large bowl, add the meat, garlic, ginger, green onions, and gyoza seasonings.
Knead the mixture with your hand until it gets sticky and pale in color.
Squeeze water out of the napa cabbage with your hands.
Add the napa cabbage to the meat mixture and mix it all together.
To Wrap Gyoza and Store
Wrap the filling with gyoza wrappers. If you never made it before, here is the tutorial on how to fold gyoza. While working on it, gyoza wrappers will become dry, so keep the wrappers under a damp towel or plastic. You also need to cover the finished gyoza with plastic. If you don't cook all the gyoza, place gyoza in a single layer on a parchment-lined baking sheet. Cover with plastic and flash-freeze until gyoza becomes solid, about for an hour. Then transfer frozen gyoza into a resealable bag to store.
To Cook Gyoza
In a large non-stick frying pan, heat oil on medium heat. When the pan is hot, arrange gyoza in a circular shape. If you place gyoza tightly together, the individual pieces won’t fall off when you flip them onto a serving plate.
When the bottom of the gyoza becomes a nice golden color, add 4 Tbsp water and cover with the lid. Let gyoza steam until most of the water evaporates.
When the water has been evaporated, remove the lid to let any remaining water evaporate. Drizzle sesame oil around the edge of the pan and cook uncovered until the bottom of the gyoza gets crispy again. The gyoza skin may look get stuck at first (from the moisture) but once water is evaporated and oil cooks the skin, gyoza will release itself.
Place a serving plate on top of the gyoza and quickly flip. Serve immediately.
You can keep the leftovers in an airtight container and store in the refrigerator for up to 2 days. I recommend cooking gyoza right before you enjoy, therefore, try to cook the amount you will be eating and keep the uncooked gyoza frozen.
What to Do with Leftover Filling
You can make quick meatballs with the leftover filling and pan-fry them.