Grilled Lamb Shwarma

Name: Grilled Lamb Shwarma
Ingredients: 1/2 cup plus 2 tablespoons extra-virgin olive oil; 6 garlic cloves, minced; Juice of 2 lemons; 1 tablespoon ground cumin; 1 tablespoon ground cardamom; 1 teaspoon Aleppo pepper or 1/2 teaspoon crushed red pepper; Freshly ground black pepper; Kosher salt; One 6- to 7-pound butterflied leg of lamb; 2 orange bell peppers, cut into 1/4-inch strips; 1 yellow bell pepper, cut into 1/4-inch strips; 3 medium red onions, thinly sliced; Yogurt-Tahini SauceSyrian Pita Bread