Cut the beef into bite-sized pieces.
Slice the onion, green onion, and carrot into thin strips.
In a bowl, mix soy sauce, sugar, minced garlic, sesame oil, and black pepper to make the marinade.
Marinate the sliced beef and vegetables in the sauce for 20 minutes.
Heat cooking oil in a pan and stir-fry the marinated meat and vegetables.
Once the meat is cooked, sprinkle sesame seeds to finish.