Cut the chicken breast into bite-sized pieces.
Cut the aged kimchi into appropriate pieces.
Julienne the onion and green onion.
Heat oil in a pan and stir-fry the chicken breast.
When the chicken is halfway cooked, add the aged kimchi and onion, then stir-fry together.
Add a little water and aged kimchi brine.
Simmer over low heat until the ingredients become tender.
Add the green onion, bring it to a boil one more time, and it's ready to serve.