01 - Arrange chicken thighs or breasts in the bottom of the slow cooker.
02 - Whisk together soy sauce, honey, ketchup, rice vinegar, sesame oil, minced garlic, grated ginger, and red pepper flakes in a medium bowl until fully incorporated.
03 - Pour the sauce mixture over the chicken, ensuring all pieces are evenly coated.
04 - Cover and cook on LOW setting for 4 hours, or HIGH for 2 hours, until chicken reaches internal temperature of 165°F and is tender.
05 - Transfer cooked chicken to a cutting board and shred or cut into bite-sized pieces. Set aside.
06 - Combine cornstarch and water in a small bowl, stirring until smooth and lump-free.
07 - Stir cornstarch slurry into the remaining sauce in the slow cooker. Return shredded chicken to the pot, mix well, and cook on HIGH for 20 to 30 minutes until sauce thickens.
08 - Transfer to serving plates or bowls and garnish with sesame seeds and sliced green onions. Serve over steamed jasmine rice or with stir-fried vegetables.