Spread out almonds and hazelnuts evenly on separate baking trays.  Bake for 5-10 minutes or until lightly golden.  Rub hazelnuts in a tea towel to remove the skins.   

Meanwhile, heat the oil in a small saucepan over a medium heat.  Add the onion and sauté for 5 minutes until softened.  Stir in the couscous and stock and bring to the boil.  Remove from the heat.  Add saffron and set aside for 10 minutes to allow the couscous to absorb the liquid.  Stir the couscous with a fork to break up any lumps. 

Transfer the couscous mixture to a large bowl.   Stir in the nuts and all the remaining ingredients to mix well.  The stuffing mixture is now ready.

To stuff and roast the chicken:
Preheat oven to 200°C (180°C fan-forced).  Spoon as much stuffing into the cavity of the chicken that is possible.  Secure the opening with a metal skewer.  Place chicken in a roasting dish.  Drizzle a little olive oil over the chicken to coat all the skin and season with salt and pepper.   Roast for 1hour 20 minutes or until juices run clear (not pink) when a skewer is inserted into the thigh.

Serve the stuffing with carved chicken pieces.