My friend threw a Prohibition-themed dinner party on Friday. I figured it would be too obvious to bring a bottle of booze, so I started looking for recipes that included alcohol. Since baking is my thing and the main course was pretty much decided, I decided to look in the dessert section of Bon Appetit, which is where I found this whiskey cake. Whiskey is my preferred spirit and thus one of few I always have on hand, so I decided this cake was the winner.

When I looked at the list of ingredients, I saw that it contained some key ingredients — espresso and vanilla — which are known for enhancing the flavor of chocolate in baked goods. The low amount of flour it called for also meant it would be a very rich, dense cake. The finished product was only about an inch thick, but the intense flavor more than compensated for the lack of volume.

Though the original recipe called for an 8-inch springform pan, mine is 9 inches so I had to make do. It only took 30 minutes for mine to bake completely. I followed the cooling instructions and frosted it the next day. While sometimes you can put the frosting on while the cake is still slightly warm, this is not one of these cases. This frosting isn’t like your traditional buttercream. No powdered sugar is involved, so it has less to keep it sturdy.

In the end, this small-but-mighty cake was a nice treat, and a sweet ending to a fun dinner.

Ingredients
1/2 cup plus Irish whiskey
6 ounces bittersweet (70 percent cocoa) chocolate (such as Scharffen Berger or Lindt), chopped
2 teaspoons instant espresso powder dissolved in 6 tablespoons hot water
1/3 cup blanched almonds (about 2 ounces), lightly toasted
6 tablespoons all purpose flour, divided
1/2 cup unsalted butter, room temperature
7 tablespoons sugar, divided
1/2 vanilla bean, or 2 teaspoons vanilla extract
3 large eggs, separated
Pinch of fine sea salt

Position rack in center of oven and preheat to 350°F. Butter and flour 8-inch-diameter springform pan.

Dissolve espresso powder in water. Set aside.

Boil 1/2 cup whiskey in small saucepan until reduced to 1/4 cup, about 2 minutes. Combine bittersweet chocolate, espresso powder mixture, and 1/4 cup boiled whiskey in small metal bowl. Place bowl over saucepan of simmering water; stir until mixture is smooth. Remove bowl from over water. Finely grind almonds with 2 tablespoons flour in processor.

Using electric mixer, beat 1/2 cup butter and 6 tablespoons vanilla sugar in medium bowl until fluffy. Beat in egg yolks 1 at a time, then sea salt. Fold in chocolate mixture, then ground almond mixture. Using clean dry beaters, beat egg whites in another bowl until soft peaks form. Gradually add 1 tablespoon vanilla sugar, beating until stiff peaks form. Fold whites into batter alternately with remaining 4 tablespoons flour in 3 additions. Transfer batter to prepared pan.

Bake cake until tester inserted into center comes out clean, about 40 minutes. Cool in pan on rack 30 minutes. Remove pan sides and cool cake completely.

Frosting
2 ounces semisweet chocolate, chopped
2 tablespoons whiskey
1/4 cup butter, room temperature

Combine semisweet chocolate and remaining whiskey in small metal bowl. Place bowl over saucepan of simmering water and stir until smooth. Remove bowl from over water. Add butter to chocolate mixture, 1 small piece at a time, whisking until each piece is melted before adding next. Place bowl over larger bowl of ice water. Using electric mixer, beat icing until thickened to spreadable consistency, about 1 minute. Spread icing over top and sides of cake. This can be made 8 hours ahead. Cover with cake dome and let stand at room temperature.