1. In a small bowl, thoroughly combine all the spices.
2. Remove giblets from chicken; clean the cavity well and pat dry with paper towels.
3. Rub the spice mixture into the chicken, both inside and out, making sure it is evenly distributed and down deep into the skin. (I cut the breast skin open and rubbed the breast meat as well)
4. Place in a re-sealable plastic bag, seal and refrigerate overnight. (I skipped this step, but it probably would have been even better if I hadn't)
5. Stuff cavity with onions and place in slow cooker.
6. Cover and cook on low for 8 hours.
7. Use a turkey baster to remove about a cup of the liquid and place it in a saucepan. Add enough cornstarch (1 tbsp maybe?) to thicken it up on low heat, makes a fab gravy!