Prepare the filling: In a large bowl, combine ground pork, finely chopped napa cabbage, grated ginger, minced garlic, light soy sauce, toasted sesame oil, white pepper, and cornstarch. Mix until all ingredients are well combined and the mixture is cohesive.

Assemble the dumplings: Take one dumpling wrapper and place approximately one tablespoon of the filling in its center. Moisten the edges of the wrapper with a little water using your finger. Fold the wrapper in half to form a half-moon shape, carefully pressing the edges together to seal. Create small pleats along the sealed edge for a traditional and secure closure.

Cook the dumplings (pan-fried method): Heat 1 tablespoon of cooking oil in a large non-stick skillet over medium-high heat. Arrange the assembled dumplings in a single layer, ensuring the flat, pleated side is facing down. Cook for 2-3 minutes until their bottoms are beautifully golden brown.

Add water and steam: Carefully pour about half a cup of water into the skillet (it will sizzle). Immediately cover the skillet with a tight-fitting lid. Reduce the heat to medium and allow the dumplings to steam for 6-8 minutes, or until the water has completely evaporated and the pork filling is thoroughly cooked.

Serve immediately: Once cooked, transfer the golden-bottomed jiaozi to a serving platter. Garnish with chopped green onions if desired, and serve hot with your favorite dipping sauce.