Preheat oven 200C. Bring lamb to room temperature and rub with half the oil. Season.
Place sweet potato in a large bowl with remaining oil and cumin. Season and toss to coat. Transfer to a baking tray lined with baking paper and cook for 25-30 minutes or until golden and tender.
To make the beetroot relish, put all the ingredients into a bowl and toss to combine.
Heat a large non-stick frying pan over medium-high heat and cook lamb for 3-4 minutes or until moisture appears on one side. Turn lamb over and cook for a further 2-3 minutes. Serve lamb with the sweet potato wedges, beetroot relish and yoghurt topped with lemon zest and extra mint.
Tips
Always use a heavy based pan for cooking as it will maintain a consistent heat. Always ensure pan is very hot before adding meat.
Any leftover meat can be thinly sliced and added to the relish. Sprinkle with a little crumbled fetta and rocket leaves for a lunchbox treat.
For a lamb steak sandwich, thinly slice the rump steaks and quickly sear in a pan. Serve on soft buns with the beetroot relish.
