Cut the chicken, potatoes, and onion into bite-sized pieces.
Add cooking oil to a pan and stir-fry the chicken.
When the chicken is half cooked, add potatoes and onion and stir-fry together.
Add soy sauce, sugar, minced garlic, and sesame oil, then stir-fry together.
Once all ingredients are cooked, plate them and finish with black sesame seeds.