Dice the peppers, onions, courgette and mix with the tomatoes in a little oil and toasted cumin seeds. Place in oven at 200c on a flat baking tray and roast for 20 mins.
Prepare a spice rub for the lamb using chilli, cumin, cinnamon, salt and turmeric. Pan fry lamb in a little oil to seal and then transfer to oven for 14 minutes or until internal temperature at thickest part of the meat reaches 52c the lamb should be blushing pink but not bloody/jelly like.
Prepare cous cous using chicken stock, salt and pepper.