Preheat the oven to 150°. In a large enamelled cast-iron casserole, heat 2 tablespoons of the oil. Season the shanks with salt and pepper. Add them to the casserole, 2 at a time, and cook over moderately high heat until browned all over, about 12 minutes. Transfer to a plate and wipe out the casserole.

Heat the remaining 2 tablespoons of oil in the casserole. Add the onion, carrots and garlic and ginger cook over moderate heat, stirring, until lightly browned, about 5 minutes. Add the other spices and cook, stirring until lightly toasted, about 1 minute. Add the tomato paste and chilli (harissa) and cook over moderately high heat, stirring, until lightly browned, about 2 minutes. Stir in the wine, orange juice & zest and boil until reduced to half.

Add the canned tomatoes and chicken stock to the casserole. Season with salt and pepper and bring to a boil. Nestle the shanks in the liquid. Cover tightly and braise in the oven for about 3 hours, basting occasionally, add the chick peas, fresh tomatoes, dates and dried mango for the last 2 hours and cook until the meat is almost falling off the bone. (5-6 hours total cooking time) Add optional chopped green olives at this stage.

Cook Couscous and let stand for 10 minutes. Fluff with a fork and stir in spring onions and pepper berry butter sprinkle almonds, mint and coriander on top.

Mound the couscous on a large platter. Arrange the shanks on the couscous and spoon the sauce on top (or serve in 2 separate dishes). Sprinkle with the remaining herb-almond mixture and serve.