Mix together all the sauce ingredients
Slice the onion, green onion, and chili pepper. Rinse the soybean sprouts and drain well
In a large pot, spread the sliced onion on the bottom. Pile the bean sprouts on top like a small mound. Place the green onion and chili pepper around the edges
Arrange the pork belly slices on top of the bean sprouts in a circular pattern
Pour the sauce over the pork
Cook over medium heat. Once the bean sprouts start releasing water, stir and mix everything together
Continue stir-frying until the pork is fully cooked, then serve hot
