1. Preheat oven to 350 degrees Fahrenheit.
2. For the 3 spice blend: In a small bowl, mix together black pepper, cinnamon and nutmeg.
3. For the marinade: In a small bowl, add soy sauce, sesame oil, ginger, garlic, salt, 1/3rd of the 3 spice mix, brown sugar and mix together.
4. Add the chicken into a ziplock bag.
5. Pour the marinade into the ziplock bag and mix the chicken and marinade.
6. Add onions into the bag.
7. Squeeze out air from the bag and leave aside for at least 2 hours to an entire day in the refrigerator.
8. Remove from refrigerator and place the chicken on a baking tray.
9. Sprinkle the rest of the 3 spice blend on the chicken.
10. Pop into the oven and bake for an hour.
11. Serve as main dish along with flavoured rice and vegetables.