Greekstyle slowroasted lamb with minty pesto

This celebratory dish (perfect for a modern Christmas menu) is slowcooked to meltinthemouth tenderness. The trick is to marinate the lamb for at least two days before cooking. Serve with new potatoes roasted with black olives, a roast vegetable salad and lightlycooked asparagus or peas. 1 whole lamb leg, about 2.8kg

1 cup sheep yoghurt, unsweetened, or regular unsweetened yoghurt

1 cup lemon juice

6 cloves garlic, crushed

2 tsp ground cumin

2 tsp sumac powder, optional

1/21⁄2 tsp cinnamon

2 Tbsp runny honey

1 tsp salt

Minty pesto

2 cups mint leaves, packed cup neutral oil tsp salt cup shelled whole pistachios, roasted, or use walnuts

1 green spring onion, coarsely chopped 1 lemon, zest only, finely grated

Method

To make the minty pesto, blend everything to a smooth puree. Cover and chill until needed — it will keep for 4 to 5 days.

Use a sharp knife to score 5 or 6 long, deep cuts across the top of the lamb.

Combine yoghurt, lemon juice, garlic, spices, honey, salt and pepper in a large bowl or ceramic dish. Add lamb and mix to coat evenly. Cover and chill for at least 48 hours or up to 3 days.

Heat oven to 130degC fanbake. Transfer lamb and marinade to a baking dish, cover and bake for 4 hours.

Remove dish from oven and increase oven temperature to 200degC fanbake. Strain lamb juices into a pot, then baste lamb with reserved juices and return to oven, uncovered, to roast for a further 30 minutes until skin is crusty and browned.

Drain off cooking juices and skim off and discard any visible fat. Pour defatted juices back over the lamb or serve in a jug. Accompany with fresh minty pesto.