Cut the pork into bite-sized pieces.
Prepare the vegetables such as onion, green onion, and chili pepper.
Make the seasoning sauce with gochujang (Korean red chili paste), soy sauce, sugar, etc.
Marinate the pork with the sauce.
Heat oil in a pan and stir-fry the pork.
Add the vegetables and stir-fry together.
Serve once all ingredients are cooked.