(note, if making into a freezer meal please follow instructions down further)
In a small bowl add the marmalade, soy sauce, red pepper flake, ginger root and garlic. Stir until smooth. Add the chicken and onion to the slow cooker. Pour over the sauce.
Cover and cook on high for 3.5 hours.
Freezer Meal Instructions:
Make the sauce as written above. Add the chicken and onion to a large ziplock bag and add the sauce, squeeze out the excess air. Place in freezer for up to a month. Thaw for about 24 hours before adding to the slow cooker. To cook, add the contents of the bag into the slow cooker, cook as directed above.
If you want to a thicker sauce, at the end of the cooking time mix together a tablespoon of water with a tablespoon of cornstarch and stir into the sauce, add the lid back on and cook for 20 minutes more.