Roast Leg of Lamb with Cumberland Rum Butter and Cumberland Sauce

Make
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1. Take a 1.25kg(2 1/2lb) lean lamb leg joint and calculate cooking time. Place on a rack in a roasting tin and open roast in a preheated oven for the calculated cooking time. Meanwhile make the rum butter. In a bowl mix together 100g(4oz) butter, softened, 25g(1oz) caster sugar, 2 pinches nutmeg, zest of 1 lemon and juice of 1/2 and 30ml(2tbsp) rum.
2. During the last 30 minutes of cooking time spread the butter over the lamb and return to the oven.
3. While the lamb is cooking make the sauce. In a pan soften 2 red onions, sliced, for 5-6 minutes. Add 150ml(ºpt) rum, 30ml(2tbsp) redcurrant jelly, the zest and juice of 1 orange and 5ml(1tsp) Worcestershire sauce.
4. Bring to the boil and simmer for 5-10 minutes until the sauce has reduced and thickened.
Eat.Serve the lamb with seasonal vegetables, new potatoes and the Cumberland sauce.