Preheat the oven to 200°C (180° fan-forced). Line a baking tray with baking paper.
Spread cauliflower onto prepared baking tray, drizzle with 1 tablespoon oil, season and toss to coat. Roast cauliflower in oven for 25 to 30 minutes or until golden and tender.
Meanwhile, in a small bowl combine remaining oil, cumin and chilli. Season and rub lamb with marinade. Heat a chargrill pan or barbecue over medium-high heat and cook lamb for 4 to 5 minutes each side or until cooked to your liking. Set aside to rest for 5 minutes. Thinly slice.
In a small food processor place garlic, yoghurt, tahini, spinach, lemon juice and zest, and parsley. Season and process until smooth, adding a little water if necessary.
Prepare rice according to packet instructions.
Divide rice, cauliflower, beetroot zucchini and rocket between 2 bowls. Top with lamb, drizzle with dressing, sprinkle with extra parsley leaves and serve with lemon wedges.