Place chopped chicken in bottom of a 4-quart crock pot.
In a small bowl, whisk together soy sauce, sugar, vinegar, garlic and ginger.
Pour over chicken.
Cover and cook on low 4 - 5 hours.
Remove chicken.
While crock pot is still warm, or left on the warm setting, if yours has one, separately mix cornstarch with water until smooth.
Slowly add into sauce in the crock pot to thicken, mixing as you add.
Return chicken to crock pot and stir to coat in sauce.
Serve over cooked brown or white rice.
Prior to serving, add green onions on top of chicken
