Step 1: Prepare the Filling : In a large mixing bowl, combine ground chicken, cabbage, green onions, carrot, garlic, and ginger. Add soy sauce, sesame oil, rice vinegar, pepper, and salt. Mix gently with a spoon or your hands until all ingredients are well combined. Avoid overmixing — this keeps the filling tender.
Step 2: Assemble the Potstickers : Place a dumpling wrapper on a clean surface. Spoon about 1 teaspoon of filling into the center. Wet the edge of the wrapper with water using your fingertip. Fold the wrapper in half to form a half-moon shape. Pinch the edges together tightly or pleat for a traditional look. Repeat until all filling is used. Keep wrappers covered with a damp towel to prevent drying.
Step 3: Cook the Potstickers : Heat 1 tablespoon of vegetable oil in a large nonstick skillet over medium-high heat. Arrange potstickers in a single layer (flat side down). Cook for 2–3 minutes until the bottoms are golden brown. Carefully pour ¼ cup of water into the pan and immediately cover with a lid. Steam for 5–6 minutes until the water evaporates and the potstickers are cooked through. Remove the lid and cook uncovered for another 1–2 minutes to crisp up the bottoms again.
Step 4: Make the Dipping Sauce : In a small bowl, whisk together soy sauce, rice vinegar, sesame oil, sugar, and chili flakes. Garnish with sesame seeds or chopped green onion.