By placing white chocolate at center stage of this opera cake, we have had to change the classic opera flavors of coffee and chocolate. But we have retained the exquisite opera texture and created a flavor system that sings: full-bodied white chocolate and sweet honey, with almonds as a back note, are presented in paper-thin layers of cake, buttercream, and mousse
Preparation: 1 hour 50 minutes, plus baking, cooling, and chilling times
- 3/4 cup slivered almonds
- 1 /2 cup plus 1 tablespoon granulated sugar, divided
- 2 large eggs, at room temperature
- 3 large egg whites, at room temperature
- 1 /4 cup cake flour
- 2 tablespoons unsalted butter, melted
- 1 /3 cup water
- 1 /4 cup granulated sugar
- 1 /4 cup honey
- 1 tablespoon B&B liqueur
- 1 cup (2 sticks) unsalted butter, softened
- 3 large egg yolks, at room temperature
- 1 /4 cup honey
White Chocolate Mousse
- 7 ounces Swiss white chocolate coarsely chopped
- 1 tablespoon B&B liqueur
White Chocolate Glaze
- 7 ounces Swiss white chocolate, coarsely chopped
- 1/4 cup heavy cream
- 1 ounce bittersweet chocolate
Make the almond biscuit
1. Position a rack in the center of the oven and preheat to 400°F. Butter a 17 1/2-by-11 1/2-inch jelly roll pan (buy -pans) and line the bottom with parchment paper. Lightly butter and flour the sheet, shaking off the excess flour. Set aside
2. Using a food processor fitted with a metal chopping blade, process the almonds to a very fine cornmeal-like texture. Place the ground almonds in a medium bowl and stir in 1/2 cup of the sugar.
3. Using a handheld electric mixer, beat 1 whole egg into the almond mixture. Beat the mixture on high speed for 1 minute. Add the second egg and beat on high speed for another minute. Scrape down the sides of the bowl and the beaters. The mixture should be pale yellow in color.
4. Place the egg whites in a 4 1/2-quart bowl of heavy-duty electric mixer fitted with the wire whisk attachment. Beat the whites on high speed until they are frothy. Slowly add the reserved tablespoon of sugar and beat until the whites are slightly glossy and stiff peaks form.
5. Sift the flour over the egg-almond mixture and, using a large rubber spatula, fold in the flour until incorporated. Gently fold in the whites in two batches. Fold in the melted butter, making sure it is completely incorporated into the batter.
6. Pour the mixture onto the prepared pan in an even layer approximately 1/4-inch thick. Tap the pan lightly on the counter and smooth to remove any air pockets.
7. Bake the cake for 10 minutes, or until lightly browned. Remove from the oven and cool on a wire rack for 10 minutes. Invert the cake onto a wire rack, peel off the parchment paper and cool completely. Cut the cake into 3 equal portions, each 5 1/2-inches wide. If the cake will not be assembled until the following day, wrap securely in plastic wrap, placing a piece of waxed paper in between each layer.
Make the sugar syrup
1. In a small heavy saucepan, combine the water, sugar, and honey. Bring to a boil and boil for 2 to 3 minutes, until the sugar is dissolved and the syrup is clear. Remove from heat and add the B&B liqueur, set aside.
Make the honey buttercream
1. Place the butter into a medium bowl and cream, using a handheld electric mixer, until completely softened and smooth, set aside.
2. In a 4 1/2-quart bowl of a heavy-duty electric mixer fitted with wire whisk attachment, beat the yolks on medium speed until pale yellow in color.
3. Spray a heatproof glass measure or ramekin with nonstick cooking spray. Place the honey in a small saucepan. Stirring constantly, bring the honey to a rolling boil over medium-high heat. Immediately pour the honey into the empty glass measure or ramekin to stop the cooking. Pour half of the honey onto the yolks, turn the mixer to high, beat for 1 minute. Turn off the mixer, add the remaining honey and beat until the bowl feels cool, for about 5 minutes. Scrape down the sides of the bowl well with a rubber spatula. Add the softened butter and beat until completely smooth. Scrape into a small bowl, cover, and reserve.
Make the white chocolate mousse
1. Melt the chopped white chocolate and the 3 tablespoons of heavy cream. Whisk gently and let cool to room temperature.
2. Place the remaining heavy cream into a 4 1/2-quart bowl of a heavy-duty electric mixer fitted with the wire whisk attachment. Add the B&B liqueur. Beat on high speed until soft peaks form.
3. Using a wire whisk, gently stir in about 1 cup of the whipped cream to the cooled white chocolate mixture. Using a rubber spatula, fold in the remaining cream. Do not over-mix or the mousse will become grainy. Cover and refrigerate until ready to use.
Assemble the cake
1. Place one of the biscuit rectangles onto a cake board of the same size. Using a pastry brush, generously soak the cake with the sugar syrup. Reserve 2 tablespoons of the honey buttercream for decoration. Place the remaining honey buttercream onto the cake and using a long, straight spatula, smooth into an even layer.
2. Place the next layer of biscuit on top and press gently into the honey buttercream layer. Again, soak with the sugar syrup. Scrape half of the white chocolate mousse onto the layer of biscuit and smooth into an even layer.
3. Place the final layer of biscuit on top and soak with sugar syrup. Smooth the remaining white chocolate mousse on top. Place the cake into the refrigerator for at least 30 minutes.
Make the white chocolate glaze
1. Melt the white chocolate with the heavy cream. Whish gently until smooth. Let cool for 10 minutes and then pour over the chilled cake. Using a long metal cake spatula, smooth out into an even layer. place the cake into the refrigerator for 30 minutes to set.
Make the chocolate decor
1. Line a baking sheet with parchment paper. Temper the chocolate. Make a small paper cone with a tiny opening at the tip and fill with the tempered bittersweet chocolate. Pipe twenty or so musical notes and or clefs onto the parchment paper. Let harden completely.
Finish the cake
1. Remove the cake from the refrigerator. Using a long sharp knife that has been heated, either in hot water (and wiped dry) or over a gas flame, slice approximately 1/4 inch off of each side of the cake to make a perfect rectangle. Slice the cake lengthwise down the center and then crosswise to make 8 equal portions.
2. Place the remaining 2 tablespoons of honey buttercream into another small paper cone with a slightly larger opening at the tip. Pipe a small dot of honey buttercream onto the center of each piece. Using a gloved hand, peel back the chocolate decor from the parchment paper and place it on the dot of buttercream. Serve immediately or refrigerate and bring to room temperature before serving.