Spiced Lamb Chops with Herbed Mashed Potatoes

Name: Spiced Lamb Chops with Herbed Mashed Potatoes
Ingredients: 4 bone-in lamb shoulder chops (6 to 8 ounces each); Kosher salt and freshly ground pepper; 1 tablespoon ras el hanout; 1 1/2 pounds Yukon Gold potatoes, peeled and cut into chunks; 4 tablespoons unsalted butter, at room temperature; Finely grated zest of 1 lemon; 3 scallions, thinly sliced; 2 tablespoons finely chopped fresh dill, plus 2 tablespoons roughly chopped; 2 tablespoons chopped fresh cilantro, plus whole leaves for topping; 2/3 cup low-fat milk; 2 tablespoons vegetable oil; Harissa, for serving