Place lamb on a plate. Add 2 teaspoons oil, 1 teaspoon cumin and 1 teaspoon coriander. Season. Turn to coat. Set aside to marinate.
Meanwhile, process cauliflower in a food processor until finely chopped. Heat remaining oil in a large frying pan over medium-high heat. Add olives and currants. Cook, stirring, for 1 minute. Add lemon rind and remaining cumin and coriander. Cook, stirring, for 1 minute. Add the cauliflower. Cook, stirring, for 2 minutes. Season well. Add half the lemon juice. Cook, covered, stirring occasionally, for 3-4 minutes or until just tender. Set aside to cool slightly.
Heat a non-stick frying pan over medium heat. Cook lamb, turning, for 6 minutes for medium or until cooked to your liking. Remove pan from heat. Drizzle with honey and remaining lemon juice. Set aside for 3 minutes to rest. Slice lamb.
Stir the shallot and herbs into cauliflower mixture. Divide among plates. Top with lamb and yoghurt, if using, and drizzle with pan juices. Sprinkle with pine nuts.