Rinse the oysters 2–3 times under running water, drain, and marinate with fish sauce, black pepper, minced garlic, and mirin.

Cut the napa cabbage into medium-sized pieces. Julienne the carrot, and slice the green onion, chili peppers, and onion.

Heat sesame oil and cooking oil in a pan. Add the napa cabbage, carrot, onion, green onion, and chili peppers. Stir-fry for 3–5 minutes.

Once the napa cabbage softens, add the marinated oysters and stir-fry until partially cooked.

Pour in 7–8 cups of water and bring to a boil. Let the flavors infuse by simmering for a few minutes.