Cut the chicken into bite-sized pieces.
Slice the onion thinly.
Add cooking oil to a pan and sauté the onion.
Add the chicken and stir-fry until cooked.
Add soy sauce, mirin, sugar, and kelp broth, then bring to a boil.
Beat the eggs and pour them evenly over the pan.
Cover with a lid and cook on low heat until the eggs are soft-set.
Serve over rice to finish.