Fennel, like certain politicians one could name, has its pestilential, never-say-die quality: you see it growing all over the city, its feathery green plumage waving from street-tree wells or creeping up faded walls. It's the kind of plant that could survive a nuclear holocaust, the kind of survivor the writer Jonathan Schell must have had in mind when he described a nuked United States as "a republic of insects and grass" at the outset of The Fate of the Earth (Knopf, 1982). He might have been optimistic about the republic part.
When we think of fennel, to be fair, we're probably not thinking of nuclear war, indestructible weeds, rotted republics, or even Hillary Clinton. We're most likely thinking about the plant's seeds, which, when dried, are a staple of the Italian kitchen and of some of the wondrous spice blends of the Indian subcontinent. But the fennel plant has roots too, pale bulbs you find in abundance at farmers markets around this time of year. The bulbs have the feel and texture of celery root and offer a licorice flavor much milder than that of the seeds, so for these reasons fennel root, sliced or shaved, is often proposed as an alternative in recipes that call for celery.
Since celery root is the last word in necessary-but-not-sufficient foodstuffs, it's easy not to bother substituting something else for it, and I never did and so I never had much use for fennel root. I always had celery root on hand, and that was enough. Then, in January, a friend served slices of roasted fennel root as a before-dinner nibble. The earth shifted slightly under my feet.
Roasting, it must be said, brings out the best in many uncooperative vegetables. It deepens and softens and adds a smoky sweetness. Beets, cauliflower, asparagus all benefit from this treatment; fennel root too.
Most of the prep work involves trimming the root end and the feathery rigging. Slice the trimmed bulbs lengthwise, about a quarter-inch thick. Rinse away any dirt, and don't worry if the slices fall apart some. Have an oven preheated to 450 degrees. Put the fennel in a single layer on a roasting pan or cookie sheet, drizzle with olive oil, sprinkle with salt and some dried thyme, and roast about 12 minutes, turning the pieces halfway through. Drizzle with a little more oil and serve.