Active Time

　　45 minutes

　　Total Time

　　2 1/2 hours

　　

Ingredients

Makes 6 servings

　　

For custards

2 1/2 oz Parmigiano-Reggiano, coarsely grated (1 1/4 cups)

　　1 cup heavy cream

　　1/2 cup whole milk

　　1 whole large egg

　　2 large egg yolks

　　1/8 teaspoon salt

　　Pinch of white pepper

　　

For soup

1 large leek (white and pale green parts only), finely chopped (1 1/4 cups)

　　1/2 cup finely chopped shallot

　　1/4 teaspoon black pepper

　　3/4 teaspoon salt

　　2 tablespoons unsalted butter

　　2 1/2 lb asparagus, trimmed and cut into 1 1/2-inch pieces

　　3 1/2 cups low-sodium chicken broth

　　1 1/2 cups water

　　1/4 cup heavy cream

　　Garnish: Parmigiano-Reggiano curls, shaved from a wedge with a vegetable peeler

　　

Special Equipment

6 (2-oz) ramekins

　　

Make custards:

Step 1

Bring cheese, cream, and milk just to a boil in a small heavy saucepan over moderate heat, stirring occasionally. Remove from heat and steep, covered, 30 minutes.

　　

Step 2

Preheat oven to 300°F.

　　

Step 3

Pour steeped cream through a very fine sieve into a bowl, pressing lightly on cheese solids and discarding them. Whisk together whole egg, yolks, salt, and white pepper in another bowl, then add steeped cream in a stream, whisking until smooth. Divide among well-buttered ramekins.

　　

Step 4

Set ramekins in a baking pan and bake in a hot water bath in middle of oven until centers of custards are completely set, 40 to 45 minutes. Transfer ramekins to a rack and cool 5 minutes (do not allow to cool longer, or custards will stick to ramekins).

　　

Make soup while cream steeps and custards bake:

Step 5

Wash chopped leek in a bowl of cold water, then lift out and drain well. Cook leek, shallot, pepper, and 1/2 teaspoon salt in butter in a 4- to 6-quart heavy pot over moderately low heat, stirring, until leek is softened, about 3 minutes. Add asparagus, broth, and water and simmer, covered, until asparagus is just tender, 10 to 12 minutes. After 2 to 4 minutes, remove 6 asparagus tips, halve lengthwise and reserve for garnish.

　　

Step 6

Purée soup in batches in a blender until smooth (use caution when blending hot liquids). Transfer to a large bowl, then pour through a sieve into cleaned pot. Stir in cream, remaining 1/4 teaspoon salt, and pepper to taste and heat over moderately low heat until hot.

　　

Serve soup with custards:

Step 7

Working with 1 custard at a time, run a thin knife around edge of each to loosen it, then invert a soup bowl over ramekin and invert custard into bowl. Repeat with remaining custards. Ladle soup around custards and garnish with reserved asparagus tips and parmesan curls.

　　Cooks' note:

　　Soup can be made 1 day ahead. Cool, uncovered, then chill, covered.