Mocha Java Blackout Cake

Kristina's birthday cake was one of two that I actually made for her, both in the same week. The first cake was for her actual birthday (The Hint 'o Mint Chocolate Cake) and this one was for for a little girl's night out she was hosting the Saturday that followed. Since she's one of my biggest cheerleaders in life, it was hard not to spoil her a little bit.
I was inspired to make this cake after gazing this beautiful cake's photo on Pittsburgh Needs Eated's blog. Along with the photo, the author mentioned that she got the recipe from The Cake Book by Tish Boyle. Not having ever heard of her, I promptly found her website and decided in an instant to not only make her Brooklyn Blackout Cake, but to buy her book, which is a keeper!

The cake was a big success, even though I rushed it a bit. I should have made the filling the night before but time just got the best of me. I was in a hurry and only let the pudding chill for about 45 minutes. As such, it wasn't as solid as I had would have liked and made for a very moist cake. This wasn't a bad thing necessarily, it just made for a messy slice (I like seeing neat layers when I cut).
Next time, I'll be sure to plan ahead.

The recipe that follows include the weight of several of the ingredients. For those of you who don't own a digital food scale, please go buy one or put it on your wish list. They aren't too expensive (less than $30). Just be sure to get one that has both metric (grams) and imperial (ounces) readouts. Seriously, weighing flour, sugar, and various other ingredients is *so* much easier than using a measuring cup or spoon! It speeds up the process and cuts down on the number of dirty utensils you have to wash too.

Mocha Java Blackout Cake
Yield 10-15 slices, depending on how small you cut the slices

Chocolate Pudding Filling
4 large egg yolks, at room temperature
2/3 cup (4.6 oz/132 g) granulated sugar
2 tablespoons plus 1/2 teaspoon cornstarch
1/8 teaspoon salt
1 cup (240 ml) black coffee
2/3 cup (160 ml) heavy cream, at room temperature
3 ounces (85 g) semisweet or bittersweet chocolate, finely chopped
1 teaspoon vanilla extract

Chocolate Blackout Cake
1 1/2 cups (6.4 oz/181 g) all-purpose flour such as Droste
1 cup (2.9 oz/85 g) non-alkalized cocoa powder
1 1/2 teaspoons baking powder
1 1/2 teaspoons baking soda
1 teaspoon salt
2 cups (14 oz/400 g) granulated sugar
2 large eggs, at room temperature
1 large egg yolk, at room temperature
1 cup (240 ml) buttermilk, at room temperature
1/2 cup (1 stick/4 oz/113 g) unsalted butter, melted
2 teaspoons vanilla extract
1 cup (240 ml) hot brewed coffee

Frosting
Adapted from Epicurious

1 tablespoon instant espresso powder or coffee crystals
2 teaspoons vanilla extract
10 ounces semisweet chocolate, chopped
1 cup (2 sticks) unsalted butter, room temperature
1 tablespoon light corn syrup
2 cups fresh powdered sugar, sifted

Optional:
Guittard Cappuccino Chips (I found them at Cost Plus World Market)

Make the Chocolate Pudding Filling

In the bowl of an electric mixer, using the paddle attachment, beat the egg yolks, sugar, cornstarch, and salt at medium speed until pale, about 1 minute (see photo below).

In a medium, heavy saucepan, combine the water and cream, and bring to a boil over medium heat. Remove the pan from the heat and whisk about 1/2 of the hot cream mixture into the yolk mixture. Whisk this mixture into the remaining cream mixture in the saucepan. Cook over medium heat, whisking constantly, until the mixture comes to a boil. Continue to boil, whisking, for 1 minute. Remove the pan from the heat and whisk in the chocolate until it is completely melted. Pass the filling through a fine-mesh sieve into a small bowl. Stir in the vanilla extract. Cover the surface of the pudding with plastic wrap, and refrigerate for at least 2 hours or overnight (do not skip this step!)

Make the Chocolate Blackout Cake

Position a rack in the center of the oven and preheat the oven to 350F. Grease the bottom and sides of two 9-inch round cake pans. Dust the pans with flour, tapping out the excess.

In the bowl of an electric mixer, sift together the flour, cocoa powder, baking powder, baking soda, and salt. Add the granulated sugar and, using the paddle attachment, mix at low speed until blended.

In a medium bowl, whisk together the eggs, egg yolk, buttermilk, melted butter, and vanilla extract. While mixing the dry ingredients at low speed, add the egg mixture in a steady steam.

Scrape down the sides of the bowl with a rubber spatula, then beat at medium speed for 1 minute, until well blended. Add the hot coffee at low speed, mixing just until blended. Remove the bowl from the mixer stand and stir the batter from the bottom of the bowl a few times to thoroughly blend the batter. Scrape the batter into the prepared pans, dividing it evenly. Smooth the batter in each pan and bake the cakes for 30 to 35 minutes, until a cake tester inserted into the center of each cake comes out clean. Cool the cakes in the pans set on a wire rack for 10 minutes.

Invert the cakes onto the rack and cool completely.

Make the Mocha Chocolate Frosting

Stir espresso powder and vanilla in small bowl until espresso dissolves. Stir chocolate in top of double boiler set over simmering water until melted and smooth. Remove from over water; cool. Using electric mixer, beat butter in large bowl until fluffy. Add espresso mixture and corn syrup; blend well, scraping down sides of bowl occasionally. Beat in melted chocolate, then powdered sugar in 3 additions. If frosting is very soft, freeze until firm enough to spread, stirring occasionally, about 10 minutes.

Cake Assembly

Using a long, serrated knife, cut each cake layer in half horizontally to make four layers. Place one cake layer, cut side up, on a serving plate. Remove the chilled pudding from the refrigerator and whisk it until it is smooth. Using a small, offset metal spatula, spread a third of the filling over the layer. Top with another cake layer repeat process remaining three layers.

Spread a thin crumb coat of frosting on the cake to "seal". Return to the refrigerator for 30 minutes or more until the frosting is set and is well chilled. Spread frosting over top and sides of cake and decorate with Cappuccino Chips, shaved chocolate, or even cake crumbs to your heart's content.