To create your Jamaican jerk seasoning, mix all ingredients together in a bowl. Store in glass jar for future use.
In your Crock-Pot® slow cooker, add chicken breast and season with salt and pepper to taste. Sprinkle 2 teaspoons of Jamaican jerk seasoning all over the chicken.
Pour 3 tablespoons of chicken broth over the chicken, then add red onions, red bell peppers, mango chunks, and torn cilantro sprigs directly on top.
Cover and cook on LOW for 5 hours.
Combine cornstarch and cold water in a small bowl to make a slurry.
Pour slurry into the slow cooker and cover for an additional 30 minutes on HIGH until sauce thickens.
Serve warm with white rice and steamed vegetables.
