Directions

1. Preheat your rear burner to high, about 450°F or so.
2. In a small, dry, frying pan, toast the thyme, fennel, rosemary, and peppercorns until they are fragrant. This will take about 3 minutes over medium-low heat. Use a mortar and pestle to grind up the spices a little before adding the salt, sage, and onion powder, and crushing it up a little more.
3. Slice the fat on the leg of lamb in a crosshatch pattern. Brush the lamb all over with the roasted garlic oil, then sprinkle the seasonings on, covering every inch, and pressing it into the slices in the fat.
4. Load up and balance your rotisserie. For some pointers on doing this, check out our video on using your rotisserie. Place the rotisserie on the grill and turn on the motor. Place a drip tray, filled with 2 cups of liquid under the rotating lamb.
5. Rotisserie the lamb for 10 to 15 minutes on high, or until a lovely crust forms. Turn the grill down, you’re aiming for a temperature of about 350°F, and continue to cook for up to 2 hours, or until an instant-read thermometer says 145°F for medium rare.
6. Use Napoleon’s PRO Heat Resistant Gloves, to remove the lamb from the grill. Remove the spit rod and forks from the roast before allowing it to rest. You don’t want residual heat to continue cooking the lamb.
7. To Make Gravy: Use the liquid in the drip tray, alongside any liquid from making vegetables to make gravy. Add ¼ cup of butter to a saucepan. Melt it over low heat and add ¼ cup of flour. Cook for 2 minutes before slowly adding the liquid from the drip tray, vegetable water, and any juices from the resting lamb. With every small addition – ¼ cup of liquid or so – whisk thoroughly. Stop adding liquid when you have reached a thick sauce that coats a spoon but is still runny. If you have added too much liquid, allow the gravy to simmer until thickened a little.
8. Slice the lamb and serve with your favorite veggies, potatoes, and gravy.