I grew up in South Africa, where lamb is the most popular meat for roasting. Every second Sunday when I was little, friends and family sat down around our big dining table and ate roast lamb. And you can't have good roast lamb without good roast potatoes! Stateside, we eat a leg of lamb infrequently because it is so expensive. When we do, it is a celebration...perfect for a holiday. Then, I did not know how well anchovies, garlic and lemon suited lamb. Now, I do.
Use either a large roasting pan with a rack to raise the lamb over the potatoes, or roast the meat on a higher shelf, with the pan catching its dripping on a lower shelf. I prefer this last, unorthodox method as more dry, hot air is able to flow around the meat and potatoes. These potatoes are delicious: crispy, and infused with the flavor of the mingled meat juices and herbs. —Marie Viljoen
Stab the lamb, 3/4 " deep, with a thin, sharp knife in about 12 places.
Using the point of your knife, stuff into each slit a couple of rosemary needles, an oregano leaf, a small piece of anchovy, and a garlic matchstick (or three). Season the surface of the leg with salt and pepper.
Grease your roasting pan with oil, and layer the potatoes in it, seasoning each layer with salt and pepper.
Place the potato pan on a shelf immediately under the shelf on which the lamb will rest.
On the shelf above, place all the oregano and leftover rosemary branches. Put the lamb leg directly on the herbs, making sure that it is squarely above the roasting pan, or you'll get fat dripping onto the oven floor.
Carefully pour the lemon juice over the leg of lamb.
Roast for 15 minutes to the lb of meat. After half an hour lower the heat to 400'F. This will (after resting) give you lamb that is pale pink inside.
When the meat is done, let it rest. Seriously. A rested lamb is a tender lamb. This is very important. Rest for at least 15 minutes, under tented foil, on a warmed dish. Keep the potatoes warm.
Carve the meat thinly, against the grain. I serve this with crabapple or quince jelly, which really confuses some people, but a fresh, mint-based salsa verde is very good, too.