Place the leg of lamb on a premium grilling rack. Season the leg generously on all sides with salt and pepper.
In a small bowl combine all the marinade ingredients and mix well.
Cut each potato crosswise into thin slices, stopping about three-quarters of the way through the potato so the slices remain attached at the bottom. In a large bowl combine the oil, paprika, rosemary, and garlic and mix well. Season with salt and pepper. Add the potatoes to the bowl and turn them in the oil mixture, coating them well on the exterior and between the slices. Transfer the potatoes to a large disposable foil pan.
Prepare the grill for indirect cooking over medium-high heat (400° to 500°F).
Prepare the grill for cooking over medium-high heat (450°F).
Brush the cooking grates clean. Place the grill rack with the lamb over indirect medium-high heat and grill, with the lid closed, for 30 minutes.
Brush the cooking grates clean. Place the grill rack with the lamb over medium-high heat and grill, with the lid closed, for 30 minutes.
After 30 minutes of grilling, place the potatoes on your cooking grates, under the grilling rack. (This will help them to cook more quickly, and they will absorb the flavorful meat juices as they cook.)
Brush the lamb with some of the marinade, then continue to grill over indirect medium-high heat, with the lid closed, brushing the lamb with the marinade every 15 minutes or so, until an instant-read thermometer registers 150°F, about 1 hour more. The potatoes should be tender when pierced with a skewer.
Brush the lamb with some of the marinade, then continue to grill over medium-high heat, with the lid closed, brushing the lamb with the marinade every 15 minutes or so, until an instant-read thermometer registers 150°F, about 1 hour more. The potatoes should be tender when pierced with a skewer.
Remove the lamb and potatoes from the grill, and rest at room temperature, indoors, for 10 minutes before slicing the lamb.
