Leg of Lamb with Fingerling Potatoes and Leeks

Name: Leg of Lamb with Fingerling Potatoes and Leeks
Ingredients: 1 (8- to 10-pound) bone-in leg of lamb, fat trimmed to 1/4-inch thick; 8 medium garlic cloves, peeled; ¼ cup packed fresh flat-leaf parsley leaves; 2 tablespoons fresh rosemary leaves; 2 tablespoons fresh oregano leaves; 2 tablespoons plus 1/4 teaspoon kosher salt, divided; 1 ½ tablespoons olive oil, divided; 1 ¼ teaspoons black pepper, divided; 2 pounds fingerling potatoes (about 6 cups), halved lengthwise; 1 ½ pounds leeks (about 3 large leeks), white and light green parts only, sliced into rounds (about 6 cups)