Chocolate Tiramisu

By exdircomp

Ingredients
Batter:
2 cups (200 grams) sifted cake flour
1 teaspoon baking soda
1/4 teaspoon salt
1/2 cup (50 grams) unsifted cocoa powder
1/2 cup lukewarm water
1/2 cup buttermilk, room temperature
1/2 cup water
2 teaspoons vanilla
2 large eggs, room temperature
4 ounces (1 stick) unsalted butter, room temperature
1 cup (200 grams) granulated sugar
1 cup (200 grams) light brown sugar, packed
Directions
Adjust rack in lower third of oven. Preheat oven to 350 degrees. Grease and flour two 8-inch round cake pans, and insert parchment paper or waxed paper to line the bottoms. Sift the flour, baking soda, and salt onto a sheet of waxed paper; set aside. Place the cocoa in a 1-quart mixing bowl. Add the 1/2 cup lukewarm water, and whisk to combine; set aside to cool. Pour the buttermilk, the 1/2 cup water, and the vanilla into a liquid cup measure. Crack the eggs into a small bowl, and whisk together to combine the yolks and whites.

Place the butter in the bowl of a heavy-duty mixer, preferably fitted with a flat beater. Cream the butter on medium speed until the butter is smooth and lighter in color, about 30 to 45 seconds. Reduce the speed to low, add the sugars in a steady stream. When all the sugar is added, stop the machine, and scrape the mixture clinging to the side of the bowl into the center. The mixture will appear sandy. Increase the speed to medium again, and cream until the mixture is light in color, is fluffy in texture, and appears as one mass, about 5 to 7 minutes. With the mixer still on medium speed, pour the eggs slowly at first. Continue to cream, scraping the sides of the bowl at least once, until the mixture appears fluffy and velvety. Stop the machine and spoon in the cooled cocoa mixture, resume at medium speed and mix just until incorporated.

Using a rubber spatula, stir in one-fourth of the flour mixture. Then one-third of the buttermilk mixture, stirring to blend together. Repeat this procedure, alternating dry and liquid. With each addition, scrape the sides of the bowl, and continue mixing until smooth, never adding liquid if any flour is visible.

Pour the batter into the pans and spread it level. Bake for 25 minutes, or until the baked surface springs back slightly when touched lightly in the center and the sides contract from the pan.

Place the cake pans on a rack to cool for 5 to 10 minutes. With mitts, tilt and rotate pans gently tapping them on the counter to see if the cake releases from sides.

Ingredients

• FOR THE CHOCOLATE MASCARPONE MOUSSE:
• 5 ounces bittersweet chocolate, cut into pieces
• 1/4 cup heavy cream
• 1/4 cup cream cheese, at room temperature
• 1 cup mascarpone cheese, at room temperature
• 2 large egg yolks, at room temperature
• 1/4 cup sugar
• FOR THE ZABAGLIONE:
• 4 large egg yolks, at room temperature
• 1 tablespoon light or dark rum
• 1/4 cup Marsala wine
• 1/2 cup plus 2 teaspoons sugar
• 1/2 cup heavy cream
• FOR ASSEMBLY:
• 1 store bought chocolate sheet cake or homemade sheet cake
• 1 cup fresh hot espresso
• 1/2 cup sugar
• 1/4 cup dark rum
• 1-ounce bittersweet or semisweet chocolate, or 1 tablespoon unsweetened cocoa powder or powdered sugar

Preparation

Step 1

To make the mousse, combine the chocolate and cream in a heatproof bowl and place in the microwave and cook on high heat for 45 seconds. Stir until chocolate is melted and the mixture is smooth and shiny.
In a large mixing bowl, beat the cream cheese, mascarpone and chocolate mixture with an electric mixer at medium to medium-high speed until soft and creamy. Pause occasionally to scrape down the sides of the bowl.
In another bowl, with clean beaters, whip the egg yolks and sugar until frothy, about 30 seconds on high. With a rubber spatula or wooden spoon, gently fold the egg mixture into the chocolate-cream cheese mixture until blended. Cover the mousse and refrigerate until ready to assemble the tiramisu. (You should have about 2 cups mousse. The mousse may be made ahead, covered, and refrigerated for up to 1 day.)

To make the zabaglione, prepare an ice water bath. Combine the yolks, rum, Marsala and 1/2 cup sugar in the top of a double boiler. Place over (not touching) barely simmering water in the lower pan and whisk vigorously, or beat with an electric mixer, until the mixture begins to foam. Whisk continuously until the mixture triples in volume and thickens to form soft mounds when the whisk is lifted, about 7 minutes. Immediately place the top of the double boiler in the ice water bath to stop the cooking. Let cool, stirring occasionally.

In a small bowl, beat the 1/2 cup heavy cream until it begins to foam. Add the remaining 2 teaspoons sugar and continue to beat until the cream holds soft peaks. Fold whipped cream into the cooled zabaglione. Cover and chill for several hours before assembling the tiramisu. You should have about 2 cups.

To assemble the dessert, in a small bowl or pitcher, add the sugar to the hot espresso. Stir well to dissolve the sugar, then add the rum.
Cut off the top of the cake and reserve for another use (see Note). Cut the cake in half horizontally. Arrange a layer of cake, cut side up, in the bottom of a deep 2 1/2-quart bowl. Moisten evenly with some of the espresso syrup. Spread half the mousse on top, and then spread half of the zabaglione on top of the mousse. Arrange the second layer of cake, again cut side up, on the mousse. Moisten well with syrup. Spread the remaining mousse on top in an even layer, followed by the remaining zabaglione. Cover and refrigerate for several hours or overnight before serving. With a vegetable peeler, cut curls of chocolate to garnish the top, or dust with cocoa.

note: The shiny top of the cake will not readily absorb syrup. If you do not cut it off, you might find dry spots in your tiramisu. But don't throw the top out! Crumble it into crumbs and place them in a 150 degrees F to 200 degrees F oven until thoroughly dry and crunchy. Use to decorate the top of the tiramisu, or save them to add to cookie batters or to scatter in pies and tarts to absorb juices.