Preheat the oven to gas mark 356°F (180°C)
1 Set your source of heat at 2/3 of its maximum power level, heat the CRISTEL roaster, and brown the leg of lamb on both sides.
2 Place the leg of lamb on the grill and position the grill in the roaster with the potatoes underneath.
3 Evenly distribute the crushed cloves of garlic, and season with salt and pepper.
4 Sprinkle the meat with thyme leaves and cook in the oven for 45 minutes.
5 Remove from the oven and leave to rest for 15 minutes before slicing.
For perfectly cooked meat, you will need to use the kitchen thermometer to check the temperature at the heart of the lamb during the cooking process:
- Rare 137°F (58°C)
- Medium rare 147°F (64°C)
- Well-done 158°F (70°C)