- Spread chicken into the crock of a slow cooker.
- Stir honey, soy sauce, ketchup, minced onion, vegetable oil, and garlic powder together in a bowl; pour over the chicken.
- Cook on Low until the chicken is tender, 3 to 4 hours.
- Remove chicken from the sauce in the slow cooker to a cutting board. Stir water and cornstarch together to dissolve cornstarch completely; pour into the sauce in the slow cooker until smooth.
- Cook on High until slightly thickened, about 10 minutes.
- Cut chicken into bite-size pieces and stir into the sauce. Sprinkle sesame seeds over the chicken and sauce mixture.