Cut the pork neck into bite-sized pieces.
Julienne the onion and green onion.
In a bowl, mix soy sauce, sugar, minced garlic, sesame oil, pepper, onion, and green onion to make the marinade.
Marinate the pork neck in the sauce for at least 30 minutes.
Heat oil in a pan and cook the marinated pork neck over medium heat until both sides are done.