It’s hard for me to look a head of cauliflower in the florets and not immediately want to cut it up and throw it in the oven.
When doused in oil and exposed to high heat, all the little crevices and fractals covering the surface — sometimes called curd because of its resemblance to cheese — sizzle until brown and wonderfully crisp. I can easily eat a half sheet-pan of roasted cauliflower on its way from oven to table, snacking on the burnished nuggets, one after the other, like potato chips.
And this is the reason cauliflower soup is a rarity in my kitchen. Why simmer the vegetable in broth when roasting it is just so grand?
This creamy cauliflower soup, however, is an exception — precisely because I roast the florets before submerging them in the broth.
The initial cooking browns the pieces, intensifying their inherent sweetness. Then, I simmer them in broth until they collapse and turn thoroughly soft. When puréed, they give the soup a rich, velvety texture that’s creamy without any dairy products.
On its own, the soup is gentle and restrained. So I usually punch it up with a bold, tangy garnish. For this version, I glazed some plum tomatoes with harissa and roasted them along with the cauliflower.
Under high heat, the tomatoes condensed, turning jammy beneath their fiery coating. Those contrasting flavors — the sweet and spicy tomatoes next to the mild, cozy soup — are what makes this so fun to eat. Every bite is a little different, some mellower, some zippier.
One thing to keep in mind: Harissa pastes vary a lot in their heat level, so taste yours before brushing it on the tomatoes. If it seems at the moderate end of the continuum (meaning you don’t immediately reach for a piece of bread to soothe your tongue), use the full amount listed. But if you’re working with a more intensely fiery paste, use the lesser amount. You can always add more later. (If you’re using a harissa powder, you can mix it with some oil to create a paste.) And if you don’t have harissa on hand, any other chile paste will work well.
It’s best to keep the tomatoes and soup separate until serving. That way, the tomatoes stay brightly scarlet in a sea of beige; it’s a soup that looks as vivid as it tastes.