Add the cornstarch mixture to the sauce in the slow cooker and stir.
Cook for an additional 15 minutes until sauce is thick and glossy.
Cook on low for 6-7 hours or high for 3-4 hours.
In a bowl, mix soy sauce, brown sugar, honey, rice vinegar, garlic, and ginger.
Mix cornstarch and water in a small bowl.
Place chicken breasts in the slow cooker.
Pour the sauce over the chicken in the slow cooker.
Remove chicken and shred with two forks.
Return shredded chicken to the slow cooker and mix with the thickened sauce.
Serve hot over rice or noodles.