Preheat the oven to 180°C/ 350°F/Gas 4. First prepare the almond stuffing. Place the couscous in a bowl, bring the chicken stock to the boil and pour it over the couscous. Stir with a fork and then set aside for 10 minutes for the couscous to swell. Meanwhile, melt the butter in a small frying pan and fry the shallot for 2-3 minutes until soft.
Fluff up the couscous and stir in the shallot and all the butter from the pan. Peel, core and chop the apple and add to the couscous with the remaining stuffing ingredients. Season and stir well.
Loosely push the couscous mixture into the neck end of the chicken. Truss the chicken.
Mix the ginger and cinnamon with the saffron water. Rub the chicken with salt and pepper, and then pour over the spiced water.
Place the chicken in a small roasting tin or dish so that it fits snugly. Spoon the chopped onions and stock around the chicken. Cover the dish with a foil tent.
Cook for 1¼ hours and then increase the oven temperature to 200°C/400°F/Gas 6. Transfer the chicken to a plate and strain the cooking liquid into a jug, reserving the onions. Return the chicken to the roasting tin with the onions, baste with a little of the cooking liquid and scatter the flaked almonds over the top. Return to the oven and cook for about 30 minutes, until the chicken is golden brown and cooked through.
Remove and discard the fat from the reserved cooking liquid, and pour into a small saucepan. Mix the flour with 30 ml/2 tbsp cold water, stir into the pan of cooking liquid and heat gently, stirring, to make a smooth sauce. Garnish the chicken and serve with the sauce.