Preheat the oven to 350°F (or medium heat on a BBQ).
Truss the lamb so it is in an evenly shaped cylinder.
Generously salt the lamb on all sides.
Combine the above spice ingredients with the remaining spic mix. Rub the mixture into the lamb, covering it entirely.
Place a rack on top of the roaster and then the lamb onto the rack. Insert the thermometer.
Roast the lamb until the internal temperature is 140° (approximately a couple hours).
Once done, remove the lamb, wrap in tinfoil and let rest for 30 minutes.