Cut the pork into bite-sized pieces and slice the onion and green onion.
Make the marinade sauce (gochujang, gochugaru, soy sauce, minced garlic, sugar, etc.).
Add the marinade to the pork and let it marinate for 10 minutes.
Heat oil in a pan and stir-fry the marinated pork.
When the pork is half-cooked, add the onion and green onion and stir-fry together.
Once the pork is fully cooked, transfer to a plate and serve.