Ingredients
-
1 tablespoon unsalted butter
-
1 cup heavy cream
-
8 ounces bittersweet chocolate, coarsely chopped
-
7 egg whites, room temperature
-
2 tablespoons granulated sugar
-
1 tablespoon cocoa powder, plus more for garnish
-
-
1 cup heavy cream
-
1/2 teaspoon pure vanilla extract
-
1 tablespoon cognac
-
confectioners' sugar, for garnish
-
1 1/2 tablespoons granulated sugar
Instructions
- Place rack in center of oven, and heat oven to 350 degrees.
- Butter an 11-by-17-inch jelly-roll pan or a 12-by-17 1/2-inch sheet pan, and line with parchment paper.
- In a small saucepan, heat 1 cup cream to a simmer.
- Add chocolate, reduce heat, and whisk until chocolate is melted.
- As soon as mixture is a uniform dark color, remove from heat and let cool for a few minutes.
- Whip egg whites and 2 tablespoons sugar to stiff, glossy peaks, about 1 1/2 minutes.
- Whisk one-quarter of the egg-white mixture into the chocolate mixture.
- Gently fold chocolate mixture back into the original egg-white mixture, and mix until smooth and well combined.
- Pour batter into the prepared pan, and spread it in an even layer with a rubber spatula.
- Bake until cake is set and puffy, 10 to 12 minutes.
- Transfer to a wire rack, and cool to room temperature.
- Lift parchment paper to remove cake from pan, and set it on work surface with long side facing edge of table.
- Using a fine-mesh sieve, lightly dust cake with cocoa powder.
- For the crème chantilly, whip the remaining 1 cup cream with the remaining 1 1/2 tablespoons sugar, the vanilla, and cognac.
- Spread evenly over entire surface of cake.
- Roll the cake lengthwise, starting at a point 2 to 3 inches over the crème chantilly.
- Roll cake another few inches, pressing against parchment paper to make a tight spiral.
- Gently peel parchment paper off as cake layer rolls away.
- Complete the roll, stopping at the far edge of the parchment paper.
- Tuck the loose parchment paper around and underneath the cylinder so it is well wrapped and can be moved easily.
- Serve immediately, or refrigerate for up to 4 hours.
- When ready to serve, transfer roulade to serving platter.
- Remove parchment paper, gently rolling cake into center of platter, with seam on bottom.
- (If roll has slumped or twisted, lay a piece of plastic over top and sides, and reshape with hands.) With a sharp knife, trim both ends of roll crosswise or on a diagonal.
- Dust top with confectioners sugar and cocoa powder, and garnish with seasonal fruit.
- To serve, cut the roll into 1-inch-thick slices, and lay flat on dessert plates; top with additional crème chantilly if desired.