Cut the thinly sliced pork belly into bite-sized pieces.
Thinly slice the onion, green onion, and spicy chili pepper.
Heat cooking oil in a pan and stir-fry minced garlic until fragrant.
Add the pork belly and grill.
When the meat is halfway cooked, add the onion, green onion, and spicy chili pepper, and stir-fry together.
Add soy sauce, red pepper powder, sugar, black pepper, and water, then mix well.
Cover with a lid and simmer over medium heat for 5 minutes.
Finish by drizzling sesame oil and sprinkling sesame seeds if desired.