Cut the chicken into bite-sized pieces.
Slice potatoes, carrots, and onions into convenient sizes.
Add cooking oil to a pot and stir-fry the chicken.
Add the vegetables and stir-fry them together.
Add soy sauce, sugar, minced garlic, pepper, and water, then bring to a boil.
Simmer on medium heat for 20 minutes.
When the sauce thickens, it's ready to serve.