Grilled Lamb

If you're cooking over charcoal, opt for natural hardwood charcoal, as Andrew Zimmern does, to give the meat a smoky flavor. Serve this dish with its wonderful homemade tortillas.
Put the lamb in a 2-gallon zippered plastic bag. Add the juice, oregano, 2 tablespoons cumin and 2 teaspoons salt; grate the lamb. Put the lamb in the refrigerator overnight.Whisk the orange juice, garlic, olive oil and onion in a blender. Place in a bowl, cover and refrigerate overnight.Combine the remaining 2 teaspoons of cumin, the remaining 1 teaspoon of salt and pepper in a small bowl.Preheat the grill to medium heat. Remove the lamb from the refrigerator; let stand for 30 minutes.Place the lamb on a grate greased with cooking spray; cover. Cook the lamb over medium heat for 1 1/2 hours or until the thermometer reads 135 ° (medium), turning frequently and drizzling with the onion mixture. Remove the lamb; let stand for 15 minutes. (The internal temperature of the lamb will rise to about 145 ° or average.) Thinly slice the lamb; sprinkle with the cumin mixture.