Heat oven to 140C/120C fan/gas 1. Remove any giblets and pull the excess fat from the duck’s cavity. Use a roasting fork or skewer to prick the skin of the duck all over – do this lightly as you don’t want to pierce the meat. Season generously inside, rub the skin with a little oil and season with salt and pepper. Stuff the cavity with the lemon halves, cinnamon, star anise and garlic. Sit the duck in a roomy roasting tin (you will be adding potatoes to the tin later). Roast the duck for 2 hrs, pricking again every now and then. Meanwhile, boil the potatoes for 10 mins until just cooked. Remove the duck from the oven and increase the heat to 220C/200C fan/gas 7. Place the duck on a board and pour off half the fat from the tin. Toss the potatoes in the tin so they are completely coated in the juices, then push them to the side of the tin. Sit the duck back in and give it a final 20-30 mins in the oven to crisp up. Meanwhile, make the apple sauce. Peel and finely slice the apples, discarding the core. Melt the butter in a pan until sizzling, add the apples and spices, then stir to coat. Pour in 100ml apple juice, cover and simmer for 10 mins, stirring occasionally. Add a splash more juice if the apples are becoming a bit dry. Cook until the apples have collapsed into a fluffy sauce. Remove the duck from the oven to a board to rest, then place the potatoes back into the oven for 20 mins to crisp up. When the duck has rested and the potatoes are brown, you are ready to carve and plate up.
