In a large mixing bowl, combine the ground pork, chopped scallions, minced ginger, minced garlic, soy sauce, sesame oil, rice vinegar, sugar, ground white pepper, and finely chopped napa cabbage. Mix everything together thoroughly until well-blended.

Allow the filling to rest for about 10 minutes to let the flavors meld together.

Take a dumpling wrapper and place about 1 tablespoon of the filling in the center. Moisten the edges of the wrapper with water, fold over and pinch the edges to seal.

Set the filled dumplings aside on a parchment-lined baking sheet.

Heat 2 tablespoons of vegetable oil in a nonstick skillet over medium heat. Arrange the dumplings in a single layer, flat-side down, and fry for about 2 to 3 minutes until the bottoms are golden brown and crispy.

Pour ½ cup of water into the skillet and cover with a lid to steam for 5 to 6 minutes until the water has mostly evaporated.

Remove the lid and press down on each dumpling with a spatula for extra crispness, cooking uncovered for an additional 2 minutes.

In a small bowl, whisk together soy sauce, rice vinegar, chili oil to taste, and sesame seeds.

Transfer the crispy dumplings to a serving plate and serve immediately with the dipping sauce.