01 - Place chicken thighs or breasts in the base of the slow cooker.
02 - In a medium bowl, whisk together soy sauce, hoisin sauce, honey, water, brown sugar, rice vinegar, garlic, ginger, sesame oil, black pepper, and red pepper flakes until well combined.
03 - Pour the sauce mixture over the chicken, ensuring each piece is evenly coated.
04 - Cover and cook on LOW for 4 hours or on HIGH for 2 hours, until chicken is tender and reaches an internal temperature of 165°F.
05 - Remove cooked chicken from the slow cooker and shred using two forks.
06 - Mix cornstarch and cold water in a small bowl to form a smooth slurry. Stir this mixture into the sauce remaining in the slow cooker.
07 - Return shredded chicken to the slow cooker and stir to coat. Cook on HIGH for an additional 15–20 minutes, until sauce has thickened to desired consistency.
08 - Serve hot over steamed rice, garnished with sliced green onions and toasted sesame seeds.