Makes 100
Dumplings
2 cups shredded cabbage
2 cups minced chives
1 cup chopped green onions
1 pound minced pork
1 pound ground beef
2 tablespoons sesame oil
1 tablespoon soy sauce
½ teaspoon salt
¼ teaspoon ground ginger
1 large egg, beaten
Mandoo, gyoza, or round Chinese dumpling wrappers
Dipping sauce
1 cup soy sauce
½ cup apple cider vinegar
Black pepper, to taste
Lightly salt the cabbage and set it aside.
Mix the other filling ingredients in a large bowl.
Wring out the cabbage until it is very dry and add it to the mixture.
Take a mandoo wrapper and lay it flat on your palm. Dip a finger into a bowl of room-temperature water and lightly coat the edge of the wrapper with water. Scoop a scant 1 tablespoon or so of the filling into the center of the wrapper. Fold the wrapper in half, lightly press the edges together to seal, and then fold 4 small vertical pleats into the edge so the mandoo will seal tightly.
Add a bit of salt to half a pot of water and boil. Add the mandoo, in batches of 12 for a regular-size soup pot, then cover the pot and bring the water to a boil again.
Add 1 cup of cold water, cover the pot, and bring it to a boil a third time. Do the same one final time. Remove the mandoo.
To make the dipping sauce: Mix a 2-to-1 ratio of soy sauce to apple cider vinegar. Add freshly ground black pepper to taste.