Ingredients

  • 2 cups chilled heavy cream
  • 4 large egg yolks
  • 3 tablespoons sugar
  • 1 teaspoon vanilla
  • 7 oz fine-quality bittersweet chocolate (not unsweetened), chopped
  • Garnish: lightly sweetened whipped cream
  • an instant-read thermometer

Method

  • Heat 3/4 cup cream in a 1-quart heavy saucepan until hot. Whisk together yolks, sugar, and a pinch of salt in a metal bowl until combined well, then add hot cream in a slow stream, whisking until combined. Transfer mixture to saucepan and cook over moderately low heat, stirring constantly, until it registers 160°F on thermometer. Pour custard through a fine-mesh sieve into a bowl and stir in vanilla.
  • Melt chocolate in a double boiler or a metal bowl set over a pan of simmering water (or in a glass bowl in a microwave at 50 percent power 3 to 5 minutes), stirring frequently. Whisk custard into chocolate until smooth, then cool.
  • Beat remaining 1 1/4 cups cream in a bowl with an electric mixer until it just holds stiff peaks. Whisk one fourth of cream into chocolate custard to lighten, then fold in remaining cream gently but thoroughly.
  • Spoon mousse into 8 (6-ounce) stemmed glasses or ramekins and chill, covered, at least 6 hours. Let stand at room temperature about 20 minutes before serving.