Heat the oven to 200C/180C fan/gas 6. Melt half the butter in a pan over a medium heat and fry the onion until soft. Add the garlic, cumin, ginger and chilli, and cook for 2 mins more. Stir in the couscous, then pour over the stock and tip in the dates and barberries. Turn off the heat, cover and leave for 15 mins for the couscous to absorb the liquid.

Use a fork to stir the walnuts, herbs and spring onions through the couscous. Leave to cool.

Stuff the chicken with the cooled couscous mixture, pushing it well into the cavity. Let the excess spill out into the tin, then slide it under the chicken to act as a trivet. Rub the remaining butter all over the chicken. Season, then roast for 1 hr 15 mins. Keep an eye on it and if the couscous stuffing that’s spilled out is getting too dark, cover it with foil.

To make the saffron butter, melt the unsalted butter, then add a generous pinch of saffron and let this sit for about 30 mins, to allow the butter to be properly infused. About 10 mins before the end of the cooking time, pour over the chicken. Serve with Greek yogurt and a green salad, if you like.