There's a 13-page (and counting) thread on eGullet (egullet.org) dedicated to roasted cauliflower (it's called 'Roasted cauliflower - tastes like French fries'). There aren't many humble, everyday vegetables that inspire entire threads, even on this food-obsessed site. While the 'tastes like French fries' claim is exaggerated (at least judging by my attempts to make the dish), the cooking process does seem to intensify the sweetness of the vegetable while removing the sulphurous qualities it gets when it's overboiled (which also makes it soggy).
The most common type of cauliflower has a creamy, off-white 'head', but it also comes in other colours, including vivid purple and green. The pale-green leaves that surround the head are usually removed before the vegetable comes to market, although they are edible. When buying cauliflower, look for firm, tightly packed florets that are evenly coloured. Although cauliflower is available year round, like other types of brassica (such as cabbage, kale and Brussels sprouts) it's considered an autumn and winter vegetable because the plant is quite sturdy and can grow even when the cooler weather kills off more delicate plants.
Multi-Michelin-starred chef Joel Robuchon turns the humble cauliflower into haute cuisine with his oscietra caviar with lobster jelly and cauliflower cream, although this is not a dish most of us would want to attempt at home. But there are many other ways to enjoy the vegetable. To make the roasted cauliflower that eGulleters are so enthusi- astic about, cut the vegetable (florets and stem) into evenly sized, fairly small pieces (about 1.5cm; it shrinks as it cooks). Mix the pieces with a good amount of melted butter and/or extra-virgin olive oil, then season with salt and pepper (and a little sliced garlic, if you like). Spread in an even layer on a baking tray and roast at 220 degrees Celsius for about 20 to 40 minutes, mixing occasionally, or until the cauliflower is tender, slightly shrivelled and brown in spots. Serve as is, or sprinkle with some freshly grated parmesan cheese.
Roasted cauliflower can also make an intensely flavoured soup. Saute a sliced leek with oil in a saucepan until soft. Add the roasted cauliflower and a peeled, diced potato. Season with salt, pepper and paprika, then stir in unsalted chicken broth. Bring to the simmer then cook until the potato and cauliflower are tender. Puree in a food processor then put the mixture through a fine-meshed food mill. Heat the pure? with freshly grated parmesan and some creme fraiche or double cream. Adjust the seasonings then ladle into bowls, drizzle with extra-virgin olive oil and serve with baguette slices that have been toasted in clarified butter.