Carrots roasted in a moderately hot oven for almost an hour become super-sweet and almost meltingly tender. We start them coated with olive oil but drizzle them with melted butter partway through roasting. The milk solids in the butter caramelize in the oven, adding a rich, nutty fragrance and flavor. Za’atar, a Middle Eastern seed and spice blend, and orange zest and juice bring complexity to the dish. Pistachios and sweet-tart pomegranate molasses are finishing touches that make this dish special. Bunch carrots—the type sold with their greens attached—are especially good here because they’re slender and fresh. If using carrots with especially thick upper portions, after halving them lengthwise, halve them again to create more uniform pieces.