“Creamy” Cauliflower and Leek Soup

This lovely soup has a silky texture and an earthy, pleasing flavor. The leeks really give it an excellent depth of flavor – and I brown the cauliflower first for even more flavor. I’ve added a bit of ground coriander and fresh thyme, but you could go bolder with curry spices or ginger. Don’t be afraid of the cream here – it is a very small amount that subtly enriches and smooths out a purée that already has a pretty nice texture. You could replace it with coconut milk or almond milk if you like.

It's always nice to have a crunchy garnish for a pureed soup. In this case, fying a few extra sliced leeks in a little olive oil until browned and crisp is an appropriate way to go. But garlic croutons or toasted nuts (especially walnuts) would be nice, too. 

Serves 4 to 6

• 2 tablespoons unsalted butter
• 2 tablespoons olive oil
• 6 (generous) cups small cauliflower florets (about 1½ lbs. or 1 medium head)
• Kosher salt
• 2 cups leeks (white and pale green parts from about 2 medium leeks), thinly sliced and well rinsed  
• 2 to 2 1/2 teaspoons fresh garlic, chopped
• 1½ to 2 teaspoons fresh thyme, chopped, plus a few extra leaves for garnish
• 1 teaspoon ground coriander
• 2½ cups low-sodium chicken broth or homemade vegetable broth
• ½ to 1 teaspoon fresh lemon juice, more to taste
• 6 tablespoons heavy cream or 1/3 cup coconut milk
• Fried leeks, chopped toasted nuts, or croutons for garnish (optional)

1. In a medium (5- to 6-quart) Dutch oven (nonstick is great if you have it), heat 1 tablespoon of the butter and 1 tablespoon of the oil over medium heat. When the butter has melted, add the cauliflower and ½ teaspoon salt. Turn the heat up just a bit, closer to medium-high, and cook, stirring frequently, until most of the florets have some browning on them, about 10 minutes. Use a slotted spoon to transfer to a plate or sheet pan.

2. Add the remaining 1 tablespoon butter and 1 tablespoon oil to the pot and reduce the heat to medium. Add the leeks (with any water still clinging to them) and ½ teaspoon salt. Stir, cover, and cook until softened, about 5 minutes. Uncover and continue cooking until just starting to brown, another 6 to 8 minutes.

3. Add the garlic, thyme, and coriander and stir until fragrant, about 30 seconds. Return the cauliflower back to the pot. Add the chicken broth or vegetable broth, 2½ cups water, and ½ teaspoon salt to the pot. Stir, bring to a boil, reduce to a simmer, and cook, uncovered, until the cauliflower is just tender (but not falling apart), 10 to 12 minutes.

4. Remove the pot from the stove and let sit for 10 minutes or so. Use an immersion blender to puree the soup right in the pot, adding half of the cream to start and more as you like. ALternatively, transfer the soup in batches to a blender. (Do not fill the blender more than two-thirds full of hot soup, and vent the lid, covering it partially with a folded dish towel to prevent hot splashes from getting on you.) Add a couple tablespoons of cream to every batch and purée on high until very smooth. Combine the batches back in the hot pot.

Season the soup with a little lemon juice, and taste for salt and lemon. Serve right away, garnished with thyme leaves, fried leeks, chopped toasted nuts, or croutons if you like.