We've finished all the potatoes from the garden, but for this recipe any large scrubbed potatoes will do. I don't bother to peel them, just cut them into chunks I can shove through the food processor attachment so they are sliced thickly. Then place them into a roasting pan and drizzle olive oil over them before scattering over some lumps of butter and a generous sprinkling of salt and pepper.
My oven is still temperamental, for a temperature of 450 I have to set it at 500 and watch closely. The leg of lamb I pierce with the point of a sharp knife and then push into each hole a small sprig of rosemary from the plant I'm overwintering above the kitchen sink, and a slice of garlic. Drizzle this with some more olive oil, grind over some salt and pepper and place the leg on one of the oven shelves with the roasting tin of potatoes directly underneath and leave to roast for about an hour. I usually turn the oven down after 15 minutes or so, but if I forget it doesn't seem to make much difference. The juices from the lamb drip over the potatoes below, soaking them in flavor and creating a wonderfully crunchy, soft dish. I'm not sure if you need to serve anything else, but I always feel the need to add something green and my kids choice is always for peas.