When I was growing up, my family made dumplings together every Sunday morning. It's a wonderfully interactive way to start the day. Dumplings are economical and simple to make and they taste especially great with the family by your side.
The filling: Place the cabbage in a food processor, add 1/2 teaspoon salt, and pulse until finely chopped but not puréed. Wrap the chopped cabbage in a clean kitchen towel and squeeze to remove juices, then transfer to a large bowl. Add ginger, garlic, scallions, and, if desired, garlic chives. Add the shrimp and pork and season with 1/4 cup soy sauce, sesame oil, and salt and pepper. Mix together by hand.
Taste the filling by poaching or frying a small amount, and adjust seasonings to taste. To prepare the dipping sauce, combine soy sauce, rice vinegar, scallions, and toasted sesame seeds in a small bowl.
To wrap, place 1 tablespoon of filling into the center of a dumpling wrapper. Wet the wrapper's edges, then fold in half to form a taco-like shape. Make a pleat on the side facing you about 20 degrees from the apex of the half-circle and seal with your fingers to the back of the skin. Repeat on the other quarter, in mirror fashion, and seal the dumpling completely, trying to eliminate any air pockets. Repeat until all filling is used.
To pan fry, heat oil in a large, nonstick pan over high heat. Add the dumplings in one layer so that they do not overlap. Add water to come halfway up the dumplings, and cover the pan. Reduce the heat to medium-high and cook until all water is evaporated and the bottoms are browned and crispy, about 10 minutes. Alternatively, the dumplings can be steamed until cooked through, about 5 minutes in a steam basket.
Transfer the dumplings to a plate and serve with a dipping sauce.