Cut the pork into bite-sized pieces.
Julienne the onion, green onion, and carrot.
Make the marinade with gochujang (Korean red chili paste), gochugaru (Korean chili flakes), soy sauce, sugar, minced garlic, and sesame oil.
Add the marinade to the pork and let it marinate for 10 minutes.
Heat oil in a pan and stir-fry the marinated pork over medium heat.
Add the vegetables and stir-fry together.
When everything is cooked through, sprinkle with sesame seeds to finish.