CHOCOLATE-AND-VANILLA ZEBRA CAKE

Chocolate-and-Vanilla Zebra Cake image

Striking stripes of vanilla and chocolate hide beneath a thick coating of glossy chocolate frosting in this dramatic cake. Best of all, it's surprisingly simple to pull off; the pattern is created by alternating spoonfuls of batter in the center of the pans.

Provided by Martha Stewart

Categories Food & Cooking Dessert & Treats Recipes Cake Recipes

Time 2h30m

Number Of Ingredients 19

Ingredients

1 stick unsalted butter, melted, plus more for pans
4 cups unbleached all-purpose flour
1 tablespoon plus 1 teaspoon baking powder
2 teaspoons kosher salt
3 large eggs, separated, plus 4 more whites, room temperature
2 1/2 cups granulated sugar
2 cups whole milk, room temperature
1/2 cup safflower oil
1 tablespoon pure vanilla extract
1/2 cup unsweetened Dutch-process cocoa powder
2/3 cup unsweetened Dutch-process cocoa powder
1 1/2 teaspoons instant espresso powder
1/2 teaspoon kosher salt
1/2 cup hot water
1 teaspoon pure vanilla extract
2 1/2 sticks unsalted butter, room temperature
1 1/2 cups confectioners' sugar
10 ounces semisweet chocolate, melted and cooled
3 tablespoons light corn syrup

Steps:

Cake: Preheat oven to 350 degrees. Brush two 9-inch round cake pans with butter. Line bottoms of pans with parchment rounds; brush parchment with butter.
Whisk together flour, baking powder, and salt until thoroughly combined, 30 seconds. In a large bowl, whisk together egg whites and granulated sugar until light, opaque, and foamy, about 2 minutes. Whisk in 1 1/2 cups milk, butter, oil, and vanilla until smooth. Add flour mixture; whisk until smooth. In another large bowl, whisk together egg yolks, 1/3 cup milk, and cocoa. Add 3 1/4 cups of vanilla batter to cocoa mixture and whisk until smooth. Whisk remaining scant 3 tablespoons milk into remaining vanilla batter.
Spoon 1/4 cup vanilla batter into center of each prepared pan. Spoon 1/4 cup chocolate batter into each center, directly on top of vanilla batter. Repeat, always spooning batter into centers of pans, and occasionally tapping pan firmly on work surface to ensure even distribution, until all batter is used (batters should appear as concentric rings).
Bake, rotating pans halfway through, until cakes are puffed slightly and a tester inserted into centers comes out clean, 35 to 40 minutes. Transfer pans to a wire rack; let cool 10 minutes. Turn cakes out onto rack, remove parchment, and let cool completely.
Frosting: Meanwhile, whisk together cocoa, espresso powder, salt, hot water, and vanilla until a smooth paste forms. Beat butter with confectioners' sugar on medium-high speed until light and fluffy. Beat in chocolate, then cocoa mixture and corn syrup, until smooth.
Trim tops of cakes flat. Transfer one cake, trimmed-side up, to a cake plate or stand lined with parchment strips. Spread 3/4 cup frosting evenly over top. Place remaining cake layer on top, trimmed-side down. Spread remaining frosting evenly over top and sides of cake. Remove parchment strips; serve. Cake can be stored, uncovered, at room temperature up to 12 hours, or refrigerated, uncovered, up to 2 days; bring to room temperature before serving.