Step 1

Preheat the oven to 425F. Butter a 17x11-inch jelly roll pan or rimmed baking sheet. Line with parchment paper and butter again and lightly flour.

Step 2

In a large mixing bowl, beat the eggs on medium-high speed until foamy. Add the almond flour and sift in the confectioners’ sugar. Beat until pale and thickened, about 3 minutes. Sift in the flour and beat just until combined.

Step 3

In a separate mixing bowl with clean beaters, beat the egg whites on high speed until frothy, about 1 minute. While beating, slowly add the sugar. Continue beating until stiff peaks form, about 3 minutes. Fold the egg whites into the flour mixture in three batches.

Step 4

Fold in the melted butter. Pour the batter into the prepared pan and gently smooth it into an even layer.

Step 5

Bake for 8 to 10 minutes or until golden brown and springy to the touch. Run a knife around the edges of the cake to loosen from the pan. Invert onto a wire cooling rack and carefully peel off the parchment paper. Let cool completely.

Step 6

In a small saucepan, whisk together the sugar and espresso powder. Whisk in the water and brandy. Place over medium heat and bring to a simmer, stirring occasionally, until the sugar is dissolved. Remove from the heat and let cool.

Step 7

In a small pot, bring 2 inches of water to a simmer over medium-high heat. Reduce the heat to low.

Step 8

Combine the chocolate and butter in a large heat-proof bowl and set over the pot making sure it doesn’t touch the water. Stir the mixture until the chocolate and butter are fully melted and combined. Remove from the heat and let cool, stirring occasionally, until thickened and spreadable but still glossy. Make the buttercream while it cools.

Step 9

In a small bowl, dissolve espresso powder in 1 tablespoon of water. Set aside.

Step 10

In the bowl of a stand mixer fitted with the whisk attachment, add the egg yolks. Beat on medium-high speed until thickened, about 6 minutes.

Step 11

Meanwhile, combine the sugar and the remaining 3 tablespoons of water in a medium saucepan and place over medium-high heat. Swirl occasionally until the sugar is dissolved. Insert a candy thermometer, and bring to a boil.

Step 12

Continue boiling the sugar until it reaches 240F. Immediately remove from the heat.

Step 13

With the mixer running, carefully and slowly pour the sugar syrup into the egg yolks in a steady stream. Beat the egg yolk mixture on medium-high speed until very stiff, gathering around the beater, and the outside of the bowl is barely warm to the touch, about 10 minutes.

Step 14

Decrease the speed to medium and add the butter, a tablespoon at a time, waiting a few seconds between each addition. (If your butter feels too cold, squeeze the piece between your fingers to warm them a bit before adding to the bowl.)

Step 15

Beat on medium speed until the buttercream is spreadable and smooth, about 3 minutes. While beating, slowly drizzle in the coffee. Scrape down the bowl and beat until well combined. Cover and set aside.

Step 16

Transfer the cooled cake to a cutting board. Cut a 4 ½-inch wide strip down one long side of the cake, creating two long pieces. Cut both pieces in half crosswise creating 4 pieces (2 large rectangles and 2 thinner strips).

Step 17

Place one large rectangle on a cake plate. Brush with a third of the cooled coffee syrup. Spread half of the coffee buttercream evenly over the cake and all the way to the edges.

Step 18

Place the two 4½-inch wide strips side-by-side on top of the buttercream. (The seam will be covered by the next layer.) Brush with half of the remaining coffee syrup. Spread half of the chocolate glaze over the cake all the way to the edges.

Step 19

Top with the remaining pieces of cake and brush with the remaining coffee syrup. Spread the remaining buttercream over the cake making it as smooth as possible. Chill for 30 minutes or until the buttercream is firm on top.

Step 20

Reheat the remaining chocolate glaze for 10 to 15 seconds in the microwave or over simmering water, just until glossy again not hot. Place 2 tablespoons in a piping bag or the corner of a ziptop bag and set aside. Spread the remaining glaze into a thin even layer over the top of the cake, making sure you go all the way to the edge. (Don’t worry if it drips over the side a bit.) Chill until firm, about 2 hours.

Step 21

When firm, trim away a bit on each side of the cake to create clean straight sides. Rewarm the glaze in the piping bag with your hands or run warm water over it. Snip the tip of the bag off and decorate by writing “Opera” on the top of the cake, or pipe as desired. Cake can be loosely covered and refrigerated for up to 4 days.