Preparation Time: Approx 10 minutes
Time to cook: Approx 2 hours 35 minutes
Preheat the oven to 180'C / 160'C Fan / Gas Mark 4-5.
Place the pork in a roasting tin, sitting the joint on the two bulbs of garlic. Tuck the garlic slivers into the scored rind or under the fat.
Roast the pork, calculating the cooking time at 30 minutes per 450g and 30 minutes extra. When cooked, allow the pork to rest for 10 minutes. Slip the backbone out before carving the pork into thick slices.
Meanwhile, for the apple and sage mash, cook the potatoes in boiling water until tender. Drain and mash. Gently cook the apples in a drop of water in a small saucepan or microwave until soft. Use a fork to lightly crush as you fold the apples into the potato together with the chopped sage and yoghurt.
To serve, spoon the mash onto warm plates and rest a generous slice of pork alongside.