This recipe is taken from the recipe posted on Simply Recipes.
Here is the Roast Leg of Lamb recipe which we bought a couple of weeks prior in Washington. The Leg of Lamb was huge, was about 5 lbs and it took me and my boys almost 5 days to finish it, that was when Ben was away on vacation. He only had two servings of it.
We had three meals with just the plain Roast Leg of Lamb with gravy and some steamed vegetable and rice and the last two meals with noodles and soup. The boys preferred to have the roast lamb in noodles and soup as I sliced the lamb very thin for them. They had hard times eating them in a steak form as they had trouble cutting them.
1 5 to 6 lbs leg of lamb, bone-in or boneless (I had boneless).
Salt and pepper to taste
1/2 cup freshly squeezed orange juice
1 cup white wine
3 cloves garlic, minced
2 teaspoons of fresh thyme or 1 teaspoon of dried thymes
2 tablespoons of fresh chopped rosemary or 1 tablespoon of dried rosemary
1/4 teaspoon of fresh ground pepper
2 tablespoons olive oil
Blend all the marinate ingredients in a blender, just a few pulses until well mixed.
The leg of lamb should be tied up with kitchen string for even baking.
Place the lamb and the marinade into a zip lock bag. Squeeze out as much of the air as possible from the bag and seal. Wrap again with another plastic bag to ensure that the marinating lamb does’nt leak. Marinate for several hours, or overnight, in the refrigerator.Remove the lamb, still in its marinade bag, from the refrigerator at least 30 minutes before putting in the oven to help bring the lamb closer to room temperature before roasting.
Preheat the oven to 425F. Arrange two racks in the oven – a middle rack to hold the lamb, and a lower rack to hold a roasting pan with which to catch the drippings. Place the empty roasting pan in the oven while the oven is pre-heating. Note that this arrangement of racks and pans, with the roast sitting directly on the oven rack, will create a natural convection of heat in the oven, causing the roast to cook more quickly than if cooked the traditional method in a rack in a roasting pan.Remove the lamb roast from its marinade bag and pat dry the marinade off the lamb with paper towels. Generously sprinkle salt and pepper on all sides of the roast. Arrange the fattiest side up, so while the lamb is cooking the fat will melt into the meat. Insert a meat thermometer into the thickest part of the roast, not touching the bone if your roast is bone-in. Place directly on middle rack of the oven, above the rack where a roasting pan is placed to catch the drippings.
Roast at 425F for 20 minutes. Then reduce the heat to 300F and roast an additional 50 to 60 minutes, about 10-12 minutes per pound. If you are cooking the roast in a roasting pan, rack or not, start the roast at 450F and then reduce the heat to 325F. Remove the roast from the oven when the thermometer reads from 130F to 135F for medium rare. Lamb should never be cooked until well done or it will be too dry.
Let the roast stand for 10 minutes before carving. Cut away the kitchen string and lice with a sharp carving knife, 1/2 inch thick slices, against the grain of the meat.
While the roast is resting, use a wooden spatula to scrape up the drippings in the roasting pan. Use the drippings to make a gravy. Place the pan on the stove on medium high heat. Pour off all but 2 tablespoons of the drippings in the pan. Dissolve 2 tablespoons of corn starch in the minimum amount of water needed to make a thin paste, about 1/4 cup.
Pour the cornstarch solutions into the pan with drippings and use a wire whisk or spatula to blend into the drippings. Stir until the gravy begins to thicken. As it thickens, slowly add water or stock or milk or cream to the pan. Alternate stirring and adding liquid, until the consistency you want. Season with salt and ground pepper.