Prepare the mousse at least four hours or up to two days in advance. Refrigerate, covered with plastic wrap.
Recipe information
Yield
makes enough for one 18-inch roulade
Ingredients
Preparation
Step 1
In the bowl of an electric mixer fitted with the whisk attachment, whip the cream to soft peaks; cover with plastic wrap and refrigerate. In a heatproof bowl set over (but not touching) simmering water, melt the chocolate. Remove from heat. In a small bowl, stir the espresso powder into the hot water until dissolved.
Step 2
In a small saucepan, bring the sugar, corn syrup, and 1 tablespoon water to a boil over medium heat, and cook until mixture registers 238°F on a candy thermometer, about 3 minutes; remove from heat.
Step 3
In the bowl of an electric mixer fitted with the whisk attachment, beat the yolks on medium speed until lightened, about 3 minutes, scraping down the sides of the bowl as needed. With the mixer on medium speed, gradually pour the sugar syrup down the side of the bowl in a slow, steady stream. With the mixer on high speed, beat until the mixture holds a ribbon-like trail on the surface for 2 seconds when the whisk is raised, about 2 minutes more. Beat in the melted chocolate and the espresso mixture to combine. Using a rubber spatula, gently fold in the chilled whipped cream until there are no streaks and the mixture is well combined.
