Cut the skirt steak into bite-sized pieces.
Julienne the onion and green onion.
Heat cooking oil in a pan and stir-fry the skirt steak.
When the meat is halfway cooked, add the onion and green onion and continue stir-frying together.
Season with soy sauce, sugar, minced garlic, and pepper.
Place the stir-fried skirt steak and vegetables over rice.
Drizzle with sesame oil and sprinkle sesame seeds to finish.