Cut the chicken into bite-sized pieces.
Cut the potatoes, carrots, and onions into bite-sized pieces.
Heat cooking oil in a pan and sauté the chicken.
When the chicken is halfway cooked, add the vegetables and stir-fry together.
Add soy sauce, sugar, garlic, and water, then bring to a boil.
Cover and simmer over medium heat until all ingredients are cooked through.
When the sauce has reduced, finish with sesame oil and pepper.