Cut the pork into bite-sized pieces.
Thinly slice the onion and green onion.
Heat oil in a pan and stir-fry the pork.
When the pork is cooked, add the onion and green onion and stir-fry together.
Season with soy sauce, gochujang (Korean chili paste), and sugar, mixing well.
When all ingredients are cooked, turn off the heat and serve on a plate.