1Combine onions, garlic, apple cider vinegar, soy sauce, brown sugar, and bay leaf in slow cooker. Season with black pepper. Place chicken thighs atop mixture. Sprinkle paprika over chicken thighs.
2Cover and cook on Low for 8 hours.
3Switch slow cooker to High. Add bok choy to chicken mixture; cook another 5 minutes. Garnish with green onion.
Footnotes
Easy Cleanup
Try using a liner in your slow cooker for easier cleanup.