In a medium bowl mix together soy sauce, water, sesame oil, minced garlic, ginger, brown sugar and corn starch.
In a large pan over medium heat, heat up oil for about 1 minute.
Add in cubed chicken and let it brown on one side for 2 minutes.
Flip chicken over and cook for another 2 minutes or until cooked completely through.
Remove chicken to a plate.
Bring pan back up to medium heat and pour in sauce.
Whisk to combine and heat through. Sauce will thicken and cook for 1 minute.
Place chicken back into the pan and stir to coat.
Cook for 1 minute and sprinkle with sesame seeds.
Serve over rice and garnish with chopped chives.