In a slow cooker, combine honey, soy sauce, ketchup, minced garlic, ground ginger, black pepper, and red pepper flakes. Stir until well mixed.
Add the chicken thighs to the slow cooker, ensuring they are coated with the sauce.
Layer the mixed vegetables on top of the chicken.
Cover and cook on low for 6-7 hours or on high for 3-4 hours, until the chicken is cooked through and tender.
Once cooked, remove the chicken and vegetables from the slow cooker and set aside.
In a small bowl, mix cornstarch and water to create a slurry. Stir this mixture into the remaining sauce in the slow cooker.
Cover and cook on high for an additional 15-20 minutes, until the sauce thickens.
Return the chicken and vegetables to the slow cooker, stirring to coat them in the thickened sauce.
Serve over cooked rice or quinoa.