Wash the napa cabbage thoroughly and cut into bite-sized pieces.
Lay out the thinly sliced pork belly.
In a steamer, layer napa cabbage and pork belly alternately, making several layers.
Pour water into the steamer, cover with the lid, and steam for 10-15 minutes.
Make a sauce using soy sauce, minced garlic, sesame oil, and red chili powder.
Serve the steamed dish with the prepared sauce.