Ingredients

1/4 cup (1/2 stick) unsalted butter

5 leeks, white and pale-green parts only, thinly sliced and rinsed well (about 3 cups)

1 white potato (about 4 ounces), peeled and cut into 1-inch pieces

Freshly ground white pepper

Large pinch nutmeg

1 small head cauliflower, cut into florets (about 4 cups)

Coarse salt

3 1/2 cups homemade or low-sodium store-bought chicken stock

1 cup low-fat buttermilk

Preparation

Melt butter in a medium saucepan over medium heat. Add leeks, and cook, stirring occasionally, 5 minutes. Add potato, 1/8 teaspoon pepper, and the nutmeg, and cook, stirring, 1 minute. Stir in cauliflower, 1/4 teaspoon salt, and 3 cups stock. Simmer, partially covered, until cauliflower has softened, 12 to 15 minutes. Using a slotted spoon, remove 2 florets, and transfer to a cutting board; thinly slice lengthwise. Set aside for garnish.

Working in batches, puree vegetable mixture in a blender, filling no more than halfway each time. Return to pan. Stir in buttermilk and remaining 1/2 cup stock. Sprinkle with 1/2 teaspoon salt, and season with pepper. Serve hot or cold, garnished with cauliflower slices.