Grilled Fennel Bathed with Riesling

Fennel (sometimes called anise) is a beautiful vegetable—a broad, white-green bulb that tapers into long, slim, celerylike stems topped with dark green, feathery fronds. The bulb is the only part that is cooked, but you can use the fronds as you would any other delicate herb such as dill. A fennel bulb is structured like a squat head of celery. For this recipe, it is sliced lengthwise into thick planks, leaving the white, pulpy end intact so that the ribs stay together. Because fennel is qu