A dash of citrus and bitters beautifully accents the caramel notes of smoky brown whiskey in this unusual cake from our magazine, Sift. A splash of cherry juice stands in for the classic maraschino cherry garnish in a Manhattan cocktail. Note: We've updated the method (as of 3/27/17) for the frosting to ensure the meringue powder is properly hydrated.
To make the cake: Preheat the oven to 325°F. Grease and flour two 9" round cake pans, or line with parchment circles and grease the parchment.
In a large mixing bowl, beat together the butter, brown sugar, salt, and baking powder until smooth. In a large measuring cup, combine the orange juice, milk, whiskey, vanilla, orange zest, and bitters; set aside. Add the eggs to the butter mixture one at a time, beating well and scraping the sides and bottom of the bowl between additions.
Add the flour mixture and the orange mixture to the butter/sugar mixture by turns, repeating until all of both are used, and scraping the sides and bottom of the bowl as you go. Beat for 1 minute at medium-high speed, then divide the batter between the prepared pans.
Bake the cake for 24 to 28 minutes, until the top springs back when lightly touched in the center and the sides just begin to pull away from the edges of the pan. Remove from the oven and cool in the pans on a rack.
For the whiskey soak: Combine the sugar and water in a small saucepan over medium heat. Bring to a boil, stirring until the sugar dissolves. Remove from the heat and stir in the orange zest, whiskey, and cherry juice.
To make the frosting: Combine the sugar, salt, and 1/2 cup of the water in a medium saucepan and bring to a boil, stirring occasionally, until the sugar dissolves. 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 whiskey, the remaining 1/2 cup water, and bitters. Sprinkle the meringue powder over the hot liquid, and 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 meringue 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. Mix in the vanilla extract and orange zest.
To assemble: 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 to be level. Brush the cut side with 2 to 3 tablespoons of the Whiskey Soak, then flip the layer over, cut side down, on 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 buttercream over it. Repeat the process with the second layer, placing it over the first.
Spread a very thin coat of frosting over the top and on the sides of the cake; it's OK if this looks messy. This is called the crumb coat. 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. Garnish with maraschino cherries and orange slices, if desired. Keep the cake chilled until 30 minutes before you wish to serve it.
