- Cook the vegetables: Put the parsnips and onions into a large pan and pour in boiling water to cover. Bring back to the boil, then cover and reduce the heat. Simmer for 5 minutes. The parsnips should be tender but firm. Drain thoroughly, then return the vegetables to the pan.
- Crisp the duck skin: While the vegetables are cooking, prick the duck skin all over without cutting into the meat. Heat the sunflower oil in a frying pan over a high heat and add the duck breasts, skin side down. Reduce the heat and cook, pressing the duck occasionally (but not turning the pieces), for 5 minutes or until the fat has run and the skin is crisp and very well browned.
- Brown the vegetables: Drizzle 2 tbsp of the duck fat over the parsnips and onions, and mix well, then set them over a low-medium heat to brown lightly and slowly while the duck finishes cooking. Stir and turn the parsnips and onions occasionally, adding seasoning to taste. The parsnips should remain firm and the pieces of onion should be tender but slightly crisp in places. Transfer to warm plates.
- Finish cooking the duck: Pour off the remaining excess fat from the frying pan and turn the duck breasts over. Cook them over a low-medium heat for 10-15 minutes, turning over once more. After 10 minutes, they will be very pink and juicy in the middle; after 15 minutes they should be cooked through but still pale pink in the middle and succulent. Season during the last minute or so. Arrange the duck over the vegetables, sliced if you prefer.
- Make the glaze: Add the brandy, blackcurrant squash or cordial and lemon juice to the frying pan. Bring to the boil over a high heat and boil for about 30 seconds, stirring in all the sediment from the pan, to reduce the mixture to a sticky, aromatic sauce. Spoon this over the duck, add parsley to garnish and serve immediately.
Duck in orange and sherry sauce: Omit the parsnips and onion wedges. Instead of the blackcurrant glaze, add 1 thinly sliced red onion to the frying pan for the final 5 minutes of cooking. Then remove the onion with the duck. Add the grated zest and juice of 2 oranges, 4 tbsp sherry, 1 tbsp sherry vinegar or balsamic vinegar, 1 tsp soft dark brown sugar and the juice of 1 lemon to the pan. Boil, stirring in all the sediment from the pan, to thicken the sauce. Spoon over the duck. Serve with new potatoes.