In a large mixing bowl, combine ground chicken, chopped Napa cabbage, green onions, garlic, ginger, soy sauce, sesame oil, rice vinegar, sugar, salt, white pepper, and cornstarch. Mix well until all ingredients are evenly distributed. Cover and refrigerate for at least 30 minutes to allow the flavors to meld.

Step 2: Fill the Gyoza Wrappers

Take a gyoza wrapper and place about 1 teaspoon of filling in the center. Dip your finger in water and lightly wet the edges of the wrapper. Fold the wrapper in half over the filling, pinching the edges together to seal, creating pleats for a traditional look. Repeat with the remaining wrappers and filling.

Step 3: Cook the Gyoza

Heat 1 tablespoon of vegetable oil in a large skillet over medium heat. Place the gyoza in the pan in a single layer, flat-side down. Fry for 2-3 minutes or until the bottoms are golden brown.

Step 4: Steam the Gyoza

Pour 1/4 cup of water into the pan and immediately cover with a lid. Let the gyoza steam for about 5 minutes or until the filling is fully cooked and the wrappers become slightly translucent.

Step 5: Serve and Enjoy

Remove the lid and let any remaining water evaporate. Transfer the gyoza to a serving plate and serve with the prepared dipping sauce. Enjoy them hot!