Peel the oranges and remove any pith. Then slice them between the membranes and divide into segments, holding the oranges over a bowl to catch the juice.
Place the couscous in a pan and pour over all the orange juice with 150ml(¼ pint) boiling water. Cover and let stand for 5 minutes, until the couscous has absorbed the liquid. Chop the mint and stir it into the couscous along with the orange segments and the black olives. Season well.
Mix the olive oil with the cumin, paprika, coriander and some salt and pepper, then brush over the lamb chops. Place the chops in a grill pan with the halved pepper.
Cook under a hot grill for 4 minutes on each side, or until the lamb is cooked to your liking. Meanwhile, steam the beans until just tender.
When the chops are done, cover with foil to keep warm while you remove the skin from the pepper. Slice it and mix into the couscous. Serve the chops with the couscous and beans.