Tender, silky, lightly charred scallions serve as an accompaniment to spice-crusted chicken, as well as a flavoring for the roasted lemon pan sauce. For best texture, crush the fennel seeds with a mortar and pestle or with the bottom of a skillet—don’t pulverize them to a powder in a spice grinder. A sprinkle of fresh herbs at the end keeps the dish bright and lively. Tarragon plays up the licorice notes of the fennel seed; cilantro will bring out the coriander. Serve with a grain or rice pilaf, crusty bread or over polenta.