Begin by carefully removing the outer leaves of the Napa cabbage. Bring a pot of water to a rolling boil and blanch the leaves for about 1 minute, allowing them to soften without losing their structure.

Once blanched, use tongs to transfer the leaves to a bowl of ice water to stop cooking. After cooling, lay them flat on a clean kitchen towel to dry.

In a large mixing bowl, combine the ground meat, minced garlic, diced carrots, and chopped green onions. Drizzle in soy sauce and cooking wine, followed by the oyster sauce, salt, and white pepper. Mix the filling thoroughly until well incorporated.

Lay one softened cabbage leaf on a clean surface, with the stem facing you. Spoon a portion of the filling near the base of the leaf, then fold up the bottom tightly like a burrito, tucking in the sides as you roll. Repeat this for each leaf until all filling is used.

Set up a steamer basket over a pot of simmering water, ensuring the water does not touch the basket. Arrange the cabbage rolls seam-side down in the steamer, leaving space between them. Cover with a lid and steam for 15-20 minutes.

While the rolls are steaming, mix equal parts oyster sauce and soy sauce with a bit of water in a small bowl. Heat in a saucepan until slightly thickened.

Once the rolls have finished steaming, carefully transfer them to a serving plate. Drizzle the optional sauce over the rolls or serve it on the side for dipping.