Remove most of the meat from the chops using a sharp boning style knife. Keep at least 3mm of fat, trimming away the excess. Leaving a small amount of fat behind will keep the skewers juicy. Cut lamb approximately into 2cm cubes. Add the lamb to a bowl with the olive oil. In a mortar and pestle, grind the Sichuan peppercorns into a coarse powder. Add the salt, ground cumin, cumin seeds, white pepper, chilli powder and gently stir. Add the spice mix to the lamb, mix all ingredients to evenly coat. If desired, cover and refrigerate for 2 to 24 hours to marinate. If using wooden skewers, soak in water for 30 minutes.
Brush the cooking grills clean with a wire brush. Grill the lamb skewers over direct medium-high heat, with the lid closed, until the lamb skewers have deeply caramelised, 8 minutes for a medium result, turning once.
Brush the cooking grills clean with a wire brush. Grill the lamb skewers over direct medium-high heat (over the fire), with the lid closed, until the lamb skewers have deeply caramelised, 8 minutes for a medium result, turning once.
Once your barbecue has preheated, brush the cooking grills clean with a wire brush. If you are using a Weber Pulse: turn the control knob(s) to one notch greater than medium (240°C-260°C). Grill the lamb skewers over direct medium-high heat, with the lid closed, until the lamb skewers have deeply caramelised, 8 minutes for a medium result, turning once.
Once your barbecue has preheated to the set temperature (SmokeFire: 270°C), brush the cooking grills clean with a wire brush. Grill the lamb skewers over medium-high heat, with the lid closed, until the lamb skewers have deeply caramelised, 8 minutes for a medium result, turning once.