Cut the cabbage, kimchi, and onion into bite-sized pieces.
Add cooking oil to a pan and stir-fry the onion and cabbage.
Add the kimchi and stir-fry together.
Add the cooked rice and mix everything evenly while stir-frying.
Season with soy sauce and gochujang (Korean red chili paste).
Finish with a drizzle of sesame oil and sprinkle of sesame seeds.