Licorice-flavored fennel, also known as anise bulb, is composed of three parts that have very different culinary uses. The most useful part is the bulb end, which looks like a cross between a peeled onion and the butt end of a bunch of celery. It can be served raw, shredded in a salad or sliced for crudites; or it can be thickly sliced and braised to tenderness in wine or broth. The stems, which ascend from the bulb, are darker and more fibrous. They don't have much use except as an addition to stocks or broth. The fronds or leaves are feathery and very delicate in flavor. They make a fanciful garnish for salad, seafood, or poultry.
When choosing fennel, look for clean, firm fennel bulbs with no signs of browning. If the tops are attached, they should look bright green and fresh. To store fennel, refrigerate in a zipper-lock plastic bag for up to 6 days.
If required to be trimmed and sliced, chop off the stems and fronds just where the pale bulb turns darker green. Save the stems and fronds for another use, or discard them. Then, prepare the bulb like an onion, cutting it in half lengthwise (through the bottom and stem ends). Trim and discard the bottom end. Place cut side down and slice cross-wise into crescent-shaped slices.