Cream of Cauliflower Soup

From: How To Read A French Fry

1 large leek
4 Tbsp butter
1 shallot, minced
2 C dry white wine
1 (1.5lb) cauliflower, trimmed and separated into small florets
1 (3/4lb) baking potato, peeled and cut into small dice
4 C water
2 C chicken stock
1 1/2 Tbsp Dijon mustard, plus more to taste
1/4 C sour cream
2 tsp salt, plus more to taste
Freshly grated nutmeg

Trim the root end and tough green leaves from the leak. Quarter it lengthwise, leaving it attached at the root end. Wash well under running water, pulling the leaves apart to rinse away all the grim. Slice the leek thin.

Combine the leek and butter in a 4-6 quart soup pot, cover and cook over medium heat, stirring occasionally to keep the leek from sticking, for 10 minutes. Add the shallot and continue cooking, covered, stirring occasionally, until the leek is very soft, about 10 more minutes.

Increase the heat to medium-high and add the wine. Cook, stirring, until the wine has reduced by about half. Add the cauliflower and potato and mix well. Add the water and stock, cover and bring to a boil. Remove the lid, reduce the heat to a simmer and cook gently until the potato and cauliflower are very tender, about 30 minutes. You should be able to smash the cauliflower with a spoon.

Transfer half of the soup to a blender and add half of the mustard, sour cream and salt. Pulse to grind, then increase the speed to puree. Transfer the puree to a medium saucepan and repeat with the remaining cauliflower mixture, mustard, sour cream and salt.

Bring the soup back to just a simmer (don't boil or the sour cream will curdle) and season to taste with additional salt and mustard. Ladle into bowls and sprinkle with nutmeg over top.