Finely chop the ground beef by hand or pulse briefly in a food processor until it has a coarse texture, then transfer to a large mixing bowl.

Mince the garlic and ginger very finely. Add to the meat along with the soy sauce, sesame oil, rice wine, salt, black pepper, and beaten eggs.

Add the breadcrumbs to the mixture and stir in one direction for about 5 minutes until the mixture becomes sticky and holds together well.

Dice the water chestnuts (if using canned, drain well) and fold them gently into the meat mixture for texture.

Wet your hands with cold water and form the mixture into 6 large meatballs, each about the size of a tennis ball. Set aside on a plate.

Cut the Napa cabbage into thick slices, separating the leafy parts from the stems.

Heat the vegetable oil in a large dutch oven or stockpot over medium-high heat. Carefully add the meatballs and sear on all sides until golden brown, about 2-3 minutes per side. Remove and set aside.

In the same pot, add the cabbage stems and stir-fry for 2 minutes, then add the leafy parts and cook for another minute.

Return the meatballs to the pot, nestling them among the cabbage. Add the chicken or vegetable stock, remaining soy sauce, and a pinch of sugar if desired.

Bring to a boil, then reduce heat to low, cover, and simmer gently for 1.5 hours, occasionally basting the meatballs with the broth.

Check that the meatballs are cooked through (internal temperature should reach 160°F) and the cabbage is melt-in-your-mouth tender.

Taste the broth and adjust seasoning with salt or soy sauce if needed. Garnish with sliced green onions and serve hot with steamed rice.