Cut the cabbage and beef into bite-sized pieces.
Julienne the onion and green onion.
Heat cooking oil in a pan and stir-fry the green onion first to bring out the aroma.
Add the beef and stir-fry over high heat.
Add the onion and cabbage and stir-fry together.
Season with soy sauce, sugar, and pepper.
Continue stir-frying until all ingredients are cooked through.
Top rice with the stir-fried mixture to serve.