How to Make It
In a skillet, toast the cumin, coriander, chile powder and Sichuan peppercorns over moderate heat, shaking the pan, until fragrant, about 2 minutes. Transfer to a spice grinder and let cool. Finely grind the spices and transfer to a bowl.
Toast the caraway in the skillet over moderate heat until fragrant, 2 minutes. Transfer to a bowl; add the cucumber, tomatoes, onion, garlic, pickling liquid and vinegar. Season with salt and pepper.
Light a grill. Thread the lamb onto metal skewers. Season with salt and pepper and then the ground spices. Grill over moderately high heat until well browned outside and pink inside, 3 minutes per side. Transfer to a platter and serve with the cucumber salad.