Purple cauliflower soup with walnut oil

Time 35 minutes
Yields Serves 4 to 6
Purple cauliflower soup with walnut oil
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THE ups and downs of cauliflower’s fortunes have, in the 500-odd years since it was introduced to Europe, been extreme -- even by mercurial food-fashion standards. Probably originating in the Far East and carried by Arab traders to the Mediterranean, it was then brought to England by Flemish weavers in the mid-1600s and later became the rage of the French court, where Louis XV’s mistress Comtesse du Barry had a consomme of veal, oxtails and cauliflower named for her. In the modern era, however, cauliflower fell into a period of obscurity, languishing upon crudite trays and within over-baked gratins.

Perhaps the nadir came at a 1990 news conference, when then-President George H.W. Bush, discussing vegetables he didn’t have to eat anymore now that he was president, gave it a thumbs down along with broccoli, Brussels sprouts and lima beans.

But cauliflower has been having a renaissance lately, thanks not only to appealing colored varieties showing up in farmers markets and grocery stores but also to chefs who have rediscovered the vegetable’s subtle charms.

Cauliflower is being spotlighted for its nuanced flavors and rich nutty notes in such dishes as cauliflower panna cotta with beluga caviar at the French Laundry; sea urchin with lobster gelee and cauliflower cream at New York’s L’Atelier de Joel Robuchon; and, from the Fat Duck in Bray, Berkshire, in England, Heston Blumenthal’s cauliflower risotto with carpaccio of cauliflower and chocolate jelly.

A far cry from crudites.

Colored varieties such as purple Graffiti, orange Cheddar and stunning green Romanesco cauliflowers that are adorning market stalls and produce aisles now in a range of sizes are not genetically engineered but rather a mixture of heirloom varieties, naturally occurring accidents and the hybrids grown from them.

Purple and orange cauliflowers are fairly recent discoveries, dating back only a few decades to separate occasions when farmers noticed an unusually colored plant growing in a white-and-green cauliflower field. Scientists then bred the colorful anomalies into distinct varieties, improving upon taste, color and hardiness.

But the Romanesco cauliflower is an heirloom and isn’t to be confused with green cauliflower, or broccoflower, which is a cross between a broccoli and a cauliflower. Romanesco is astonishing in appearance, as much for its composition as for its color. Lime-green in hue, a head (or curd) of Romanesco is a near-perfect example of naturally occurring fractal: a fragmented geometric shape composed of smaller parts that are copies of the whole. The cauliflower resembles an M.C. Escher print more than something you’d find naturally occurring in your vegetable garden.

“The guys at Caltech come down and study them,” says Alex Weiser of Weiser Family Farms, in whose farmers market stands you’ll find all three varieties of cauliflower. “Something about the Mandelbrot theory.” But you don’t need a degree in mathematics to cook them. Whether they’re fully grown or beautiful babies, Weiser prefers his cauliflower roasted, with just a little sea salt and olive oil splashed on before they’re put in a hot oven.

The new cauliflower colors not only liven up the plate visually but also are significant indicators of flavor and health benefits.

Purple cauliflower, which gets its distinctive deep lavender color from anthocyanins, the antioxidant also found in red wine, has a milder flavor than white cauliflower -- it’s sweeter, nuttier and without the bitterness sometimes found in white cauliflower. Steamed, simmered or roasted, it retains its lavender beauty, especially with a little lemon or vinegar splashed on before cooking (though some purple varieties can turn green if overcooked).

Orange cauliflower varieties such as Cheddar are similarly mild and somewhat sweet, with a good dose of beta carotene. Romanesco, meanwhile, has a brighter, more floral flavor than traditional white. And even fully grown, all three varieties of cauliflower require shorter cooking times than the white cauliflower.


Chameleon characteristics

WHETHER it comes in brilliant green, earthy pale orange, shades of violet or traditional matte white, cauliflower is delicious lightly steamed or roasted, and it’s a wonderfully adaptive vegetable. A favorite in Indian koftas (croquettes) and curries, the cool creaminess of the cauliflower is the perfect foil for those dishes’ layers of spice and heat.

But cauliflower can also stand on its own, especially when its flavors are gently milked into a subtle cream or an ethereal panna cotta. Dairy provides a wonderful and gentle medium for cauliflower, bringing out its mellow yet distinctive essence.

In addition, the vegetable’s silky notes play off caviar particularly well. It also provides a terrific backdrop to other rich ingredients, such as sea urchin, lobster and truffles.

If black truffles aren’t your (or your accountant’s) cup of tea, try finishing a simple cauliflower soup with walnut oil. Gently simmer purple cauliflower and purple potatoes in milk with a few leeks that have been sauteed in butter, then simply puree and serve drizzled with a little oil. The oil’s richness plays off the smooth, subtle flavors of the soup, the walnut accentuating the inherent nuttiness of the cauliflower.

Or roast a whole chicken with a few heads of baby orange cauliflower, some tiny orange, purple and white carrots and a handful of toasted hazelnuts. The earthy notes of the chicken, the caramelized carrots and the crunchy hazelnuts bring out the subtle flavor of the cauliflower. And the dish looks remarkable, like a rustic, burnished feast.

Show off the glorious Romanesco cauliflower in a warm salad with Brussels sprouts pulled together by a luscious compound butter of mustard, lemon, marjoram and capers. Separated into individual florets and cooked gently, the fractals of the Romanesco become brilliant green, their geometric shapes strewn in the landscape of the salad like geodes.

When selecting cauliflower, look for heads without any speckles, and leaves that are strong and not wilted. White cauliflower is widely available year-round and thanks to their popularity with chefs, the purple, orange and Romanesco varieties are becoming increasingly easy to find. The colored varieties are seasonal and best from January through March. Most Whole Foods and Bristol Farms stores carry colored cauliflower in season. Farmers market availability varies according to weather; Weiser stands at the Santa Monica, Pasadena, Hollywood, Claremont, Beverly Hills and Venice farmers markets usually carry all three colors this time of year.

With so many colorful variations, cauliflower is one vegetable that shouldn’t have to worry ever again about the vicissitudes of style.


In a medium saucepan, melt butter over medium-low heat, add leeks and cook until soft, about 5 minutes. Add cauliflower, milk and salt and bring to a simmer. Cover and simmer on low heat until vegetables are soft, about 25 minutes. Do not boil.


Remove the vegetables from the heat, let cool slightly and puree them in a blender, with an immersion blender or in a food mill. (If using an immersion blender, cover with a towel to avoid splattering.)


If serving warm, reheat gently and serve with a drizzle of walnut oil. If serving cold, chill in the refrigerator before serving (also with walnut oil).

Purple cauliflower and potatoes are available at farmers markets and select supermarkets. White cauliflower and potatoes can be used.