Grilled Leg of Lamb with Ancho Chile Marinade

Name: Grilled Leg of Lamb with Ancho Chile Marinade
Ingredients: 1/2 cup dry white wine; 1/4 cup extra-virgin olive oil; 8 garlic cloves, peeled; 4 tablespoons fresh oregano leaves, divided; 3 tablespoons ancho chile powder*; 2 tablespoons fresh lemon juice; 2 green onions, divided; 1 tablespoon (packed) dark brown sugar; 2 1/2 teaspoons coarse kosher salt; 2 1/2 teaspoons freshly ground black pepper; 1 4 1/2-pound boneless leg of lamb, opened flat like a book, trimmed of all fat and sinew (3 1/2 pounds after trimming)