When you cut meat into cubes for kabobs, make sure you cut them into good-sized cubes, at least 1 1/2 inches thick. These are large enough to hold up to grilling and to not fall through the grill rack if one slips off the skewer. For sturdy kabobs that are easy to turn, lay two skewers next to each other and thread the meat and vegetables on both. The food cannot twist on the skewers. You will need twice the number of skewers called for in the recipe.
1/2 cup canola oil
4 cloves garlic, minced
4 tbsp. grated fresh ginger
2 tbsp. ground coriander
4 tsp. ground cumin
1/8 tsp. ground cinnamon
1/8 tsp. ground cardamom
Vegetable oil cooking spray
2 small onions, cut into 6 wedges
2 large green bell peppers, cut into 1 1/2-inch chunks
2 large red bell peppers, cut into 1 1/2-inch chunks
12 (12-inch) skewers
Combine the oil, garlic, ginger, coriander, cumin, cinnamon, and cardamom in a large glass or ceramic dish. Sprinkle the lamb generously with salt and pepper and add the lamb to the marinade. Toss to coat, cover, and refrigerate for at least 2 hours and as long as 6 hours.
Prepare a charcoal or gas grill. Lightly spray the grill rack with vegetable oil cooking spray. The coals should be moderately hot to hot.
Thread the lamb, onion wedges, and peppers onto skewers, beginning and ending with the meat. Grill for 8 to 10 minutes, turning several times with tongs and brushing 2 or 3 times with any excess marinade during the first few minutes of grilling. Cook until lamb is medium-rare and the vegetables are tender. Serve immediately.