Place chicken in slow cooker. Mix in a bowl sugar, soy sauce, vinegar, ginger, garlic, pepper. Once mixed together well pour over chicken. Cook on high for about 2 1/2 hours (or until chicken is cooked all the way through)
Remove chicken from crockpot and cut in slices (as pictured above)
Mix cornstarch and water in a small bowl.
Put the remaining sauce in a saucepan and bring to a boil. Slowly add the cornstarch mixture and continue to stir until sauce is thickened.
Put chicken over steamed rice and drizzle sauce over the top. And drizzle even more if you are addicted to sauces like I am!