Active Time

　　45 min

　　Total Time

　　1 3/4 hr

　　The coffee foam attains its consistency with the help of a charged siphon. If you don't own one, don't worry—the coffee mixture can also be served, chilled but unfoamed, as a sauce.

　　Active time: 45 min Start to finish: 1 3/4 hr

　　

Ingredients

Makes 8 servings

　　

For coffee foam

1/2 cup green coffee beans

　　1/4 cup packed light brown sugar

　　1 (13 1/2-oz) can unsweetened coconut milk

　　1/2 cup heavy cream

　　

For chocolate ganache cakes

4 whole large eggs

　　4 large egg yolks

　　1/2 cup granulated sugar

　　1/2 lb Valrhona or Lindt bittersweet chocolate (not unsweetened), chopped

　　2 sticks (1 cup) unsalted butter, cut into pieces

　　1/2 cup cake flour (not self-rising)

　　Special equipment: 1-liter whipped-cream siphon and 2 gas (N2O) chargers

　　

Make coffee foam:

Step 1

Toast coffee beans with brown sugar in a 2-quart heavy saucepan over moderately low heat, stirring constantly to evenly toast beans, until sugar is melted and beans are color of almond skins, 12 to 15 minutes.

　　

Step 2

Add coconut milk and simmer (mixture will bubble up and steam, and sugar will harden), stirring occasionally, until sugar is dissolved, about 5 minutes. Pour through a sieve into a metal bowl and stir in cream.

　　

Step 3

Set metal bowl in a larger bowl of ice and cold water to chill, stirring occasionally.

　　

Step 4

Transfer sauce to siphon and screw on top tightly. Unscrew charge holder from head and put in a charger. Reattach charge holder and screw on tightly. Gas will be released into siphon (with a whooshing sound) within a few seconds. Chill filled siphon at least 1 hour to produce a stiffer foam. Remove and discard first charger. (As you unscrew charge holder, you’ll hear a brief hissing sound.) If fitting from holder comes out attached to charger, just remove charger and reattach fitting. Screw on second charger and chill at least 15 minutes (longer if a test of foam is not thick enough).

　　

Make cakes:

Step 5

Preheat oven to 400°F. Butter and flour 8 (4-oz) ramekins, knocking out excess flour, and put on a baking sheet.

　　

Step 6

Whisk together whole eggs, yolks, and sugar until combined well.

　　

Step 7

Melt chocolate and butter in a double boiler or a metal bowl set over a saucepan of simmering water, stirring.

　　

Step 8

Remove top of double boiler or bowl from heat and whisk egg mixture into it. Sift flour evenly over chocolate mixture and fold in until just combined.

　　

Step 9

Divide among ramekins and bake in middle of oven until cakes begin to puff but centers are not set, 12 to 13 minutes.

　　

Step 10

Shake siphon well, about 1 minute. Turn upside down and press lever to fill a bowl with coffee foam.

　　

Step 11

Serve cakes in ramekins with coffee foam on the side.