Creamy vanilla poured over rich, coffee-infused chocolate: the White Russian cocktail has always been in the realm of dessert. This tantalizing recipe from our magazine, Sift, makes it official by transforming cocktail into cake. Note: We have updated the frosting method (as of 3/27/17) to ensure the meringue powder is properly hydrated.
Preheat the oven to 350°F. Grease and flour three 8" round cake pans.
To make the vanilla batter: In a large mixing bowl, beat together the butter, sugar, vegetable oil, baking powder, and salt.
In a small bowl whisk together the egg whites, whole egg, and vanilla. With the mixer running at medium-low speed, slowly add the egg mixture to the butter/sugar mixture.
Add the flour alternately with the yogurt, beginning and ending with the flour. Scrape down the bowl and mix for another 30 seconds. Divide the batter evenly among the prepared pans.
For the chocolate batter: Whisk together the flour, baking powder, baking soda, salt, cocoa, espresso powder, and sugar. Add the butter and beat at medium speed until the mixture looks sandy. Mix in the vegetable oil and vanilla.
Combine the milk with the coffee and add gradually, with the mixer running at low speed. Increase the speed to medium-high and beat for 1 minute. Add the eggs, one at a time, beating well after each. Scrape the bowl, then beat for 30 seconds more.
Scoop the batter in a random pattern into each of the three pans until all is used. Using a table knife or spatula, swirl the chocolate batter through the vanilla very lightly, taking two or three turns through each pan.
Place the layers on the center rack of the oven and bake for 24 to 26 minutes, until they just begin to pull away from the side of the pan and the top springs back when lightly touched. Remove from the oven and cool completely on a rack, still in the pans.
To make the Kahlua soak: In a small saucepan set over medium heat, combine the sugar and water, stirring occasionally until the sugar dissolves. Remove from the heat, add the Kahlua, and cool to room temperature.
To make the frosting: In a small bowl, combine the espresso powder and chopped chocolate. Heat the cream to a simmer and pour over the ingredients in the bowl. Let sit for 2 minutes, then stir or whisk until smooth. Stir in 1 tablespoon of the Kahlua and set the mixture aside to cool while you make the buttercream.
Combine the sugar, salt, and half of the water in a medium saucepan and bring to a boil, stirring occasionally. Boil for 3 to 5 minutes without further stirring, until the syrup reaches 240°F, then pour the hot syrup into the bowl of a stand mixer fitted with a whisk.
Add the remaining tablespoon of Kahlua, the remaining 1/2 cup of water, and sprinkle the meringue powder over the hot liquid. Whisk slowly until the powder dissolves.
Increase the mixer's speed to medium and beat until the mixture begins to get foamy, then turns white and increases in volume. Turn the mixer's speed to high, and beat for 3 to 4 minutes, until the mixture is thick and glossy-looking.
Add the butter a few tablespoons at a time, with the mixer running. The mixture will thin out and look a little curdled for awhile; don't let that throw you. Keep the mixer going and add the rest of the butter. If you want more frosting or are planning to serve the cake in a warm environment, beat in the additional 1/2 cup shortening or butter. The frosting will transform itself into a smooth, silky, fluffy mass as you go.
Divide the frosting in half, and stir the cooled chocolate mixture into one of the halves.
Turn the cake layers out of their pans and place them right side up. If the layers have a dome on the top, use a long, serrated knife to trim them level. Brush the trimmed side with 2 to 3 tablespoons of the Kahlua soak, then flip one of the layers over, trimmed side down, onto a serving plate.
Brush the other side of the layer with more of the soak, and once it's absorbed, spread a 3/8"-thick layer of the chocolate frosting over it. Repeat the trimming and soaking process with the second layer, placing it over the first. Frost the top of that layer with a layer of the white frosting.
Trim, soak, and place the last layer on top of the cake. Use the white frosting to thinly coat the top and halfway down the side of the cake. It's OK if this looks messy; this is called a crumb coat. Use the chocolate frosting to thinly coat the bottom layer. Refrigerate the cake for 30 minutes to allow the crumb coat to firm up.
After you can touch the crumb coat without leaving a fingerprint, use the rest of the frosting to put a finish layer on the top and sides of the cake. The White Russian cocktail is lighter on top and darker on the bottom, so repeat the white frosting on top and chocolate on the bottom, mixing them together a bit in the middle.
To make the icing: Put the water and corn syrup in a heatproof 2-cup measure, stirring to combine. Microwave on high for 60 seconds. Add the chocolate and stir until it melts. Gradually whisk in the confectioners' sugar, until the icing is completely smooth, creamy white, and lump-free. Stir in the vanilla and salt. If the icing starts to set, microwave it in 5-second pulses, stirring after each, until pourable. Drizzle over the chilled, frosted cake and let it run down the sides.
Store the cake in the refrigerator until 30 minutes before you wish to serve it. Place plastic wrap on any cut edges of leftover cake, and refrigerate for up to 1 week.
