Remove the Lamb from the fridge 30 minutes before cooking and check the weight to calculate your roasting time.
Preheat your oven to 220C/ 200C Fan/ Gas 7. Warm through the Blackcurrant Preserve with the Worcestershire Sauce and set aside.
Poke the Lamb all over with a small knife, making pockets about 4cm deep. Put A slice of Garlic and a couple of uncut Rosemary Leaves in each pocket.
Place the onions in the base of a large roasting dish and sit the Lamb on top. Drizzle with the Olive Oil and season well.
Roast, covered with foil, for 30 minutes.
Remove the foil and reduce the heat to 180C/ 160C fan/ Gas 4.
Return to the oven for 20 minutes per kg for Rare Lamb, 30 minutes per kg for Medium or 40 minutes per kg for well done.
In the last 5 minutes of cooking, brush the Lamb with half of the Blackcurrant Glaze.
Allow to rest for 15 minutes, covered with foil, before serving with the leftover glaze. Delicious alongside Fortnum’s Welsh Rarebit potato gratin.
Perfectly Paired With...
For a classic partner, try the soft tannins and gorgeous acidity of our dark cherry and plummy fruit-filled Chianti Classico. For a fresher pairing, try our toasty Chardonnay with crisp lemon fruit notes, and of course, Mint Sauce is a must.