Cut the beef belly into bite-sized pieces.
Slice the onion and green onion thinly.
Add cooking oil to a pan and sauté the onion and green onion.
Add the beef belly and stir-fry over high heat.
Add soy sauce, sugar, minced garlic, and pepper, and mix well.
Once the ingredients are cooked, drizzle with sesame oil.
Sprinkle sesame seeds to finish.