Start by trimming off silver membranes. There's usually a lot of membranes, but not so much fat. If needed, truss the roast with butcher's twine.
Now dry brine the roast (0.5 tsp salt per lb of meat), and place it on a plate in the fridge. The dry brining is best done the night before, but if you’re short on time it needs at least 2 hours.
Brush an even layer of mustard on all sides, and then sprinkle lemon pepper all around. I typically go heavy on the lemon pepper.
Fire up your grill, make sure you configure it for indirect heat. Have it running at 225-240° F. For a 2.2 lb. roast this takes roughly 2 hours. Place a thermometer in the thickest part of the meat. Place 2-3 wood chunks on the glowing embers for smoke flavor. I usually use apple or cherry wood.
Put the lid back on and smoke the lamb until its inner temperature hits 60° C / 140° F. Bring it in and let it rest for 30 minutes on the kitchen counter before slicing. I recommend serving it with a tasty Hollandaise sauce.