Cut the pork into bite-sized pieces.
Slice the onion and green onion thinly.
Add oil to a pan and stir-fry the pork.
Add the onion and green onion and stir-fry together.
Add gochujang, soy sauce, minced garlic, sugar, and chili powder; stir-fry until the seasoning blends well.
Serve the finished spicy pork stir-fry in a dish.