The holidays are coming, and a lot of people are asking for an impressive dessert to serve to their guests. The following isn't a very hard cake to make, just time-consuming. It's very impressive and VERY tasty. If you like coffee. Which I do. A lot. The various components can be made ahead of time, and kept refrigerated.
It's called an Opera Cake. It's a classic French dessert created by Louis Clichy. He, of course, called it the Clichy. However, it was made popular by a French bakery called Dalloyau, and they called it an Opera Cake.
The traditional recipe calls for an almond biscuit, or joconde, but since I avoid all things with almonds, I make it using a sponge cake. Use your favorite recipe. I prefer Rose Levy Berenbaum's sponge from her book, "The Cake Bible." You'll need a recipe that is baked in a half-sheet pan, or enough to cut 3 rectangles measuring 6 by 12 inches.
You'll also need a recipe for coffee buttercream (there is a coffee variation of one of Rose Levy Berenbaum's recipes for buttercream in "The Cake Bible"), coffee syrup (I wrote one from my pastry school out below), and chocolate ganache (pastry school recipe written out below).
Coffee Syrup
1 teaspoon instant-espresso powder
½ cup plus 1 tablespoon water
½ cup granulated sugar
¼ cup Cognac or other brandy
Stir together espresso powder and 1 tablespoon water until powder is dissolved. Bring sugar and remaining ½ cup water to a boil in a 1- to 2-quart heavy saucepan, stirring until sugar is dissolved. Reduce heat and simmer syrup, without stirring, 5 minutes. Remove from heat and stir in Cognac and coffee mixture.
Chocolate Ganache
6 tablespoons unsalted butter
7 oz fine-quality bittersweet chocolate (70 to 71% cacao), coarsely chopped
Melt butter and all but 2 tablespoons chopped chocolate in a double boiler or in a metal bowl set over a saucepan of barely simmering water, stirring occasionally, until smooth. Remove top of double boiler and stir in remaining 2 tablespoons chocolate until smooth, then cool glaze until room temperature but still liquid.
Assembling the Cake
- Place one rectangle of cake on a cake plate. Spread a thin layer of ganache on one side, and refrigerate to set.
- Remove from refrigerator, and place cake chocolate-side-down on a cardboard cake plate just a fraction smaller than the cake rectangle. Brush with one-third of the coffee syrup.
- Spread a layer of coffee buttercream about ¼ inch thick.
- Place a second cake layer on top, brush with half of the remaining syrup, and spread another ¼ inch thick layer of buttercream.
- Top with the third cake layer and brush with remaining syrup. Spread with a ¼ inch thick layer of buttercream. Smooth the top carefully with a palette knife. Refrigerate or freeze until firm.
- Place assembled cake on a baking rack set inside a half-sheet pan. Pour the warm ganache over the cake. Pass a palette knife over the top of the cake ONLY ONCE and tap the tray to smooth the glaze. Refrigerate to set.
- Remove from the rack and trim the sides of the cake neatly and squarely with a hot knife. Pour remaining ganache into a piping bag with a small round tip, and pipe the word "Opera" (in cursive handwriting) on the top of the cake. Refrigerate until ready to serve.