Chocolate Zebra Cake
This cake is just plain fun to make, admire, and eat. The name comes from the four thin layers of dark chocolate cake filled with white chocolate cream. Lines of dark chocolate zigzag across the top.
Mixing time: 15 minutes for cake, filling, and frosting Baking: 350°F (180°C/gas mark 4) for about 15 minutes
For the Cake:
For the Filling and Frosting:
To Make the Cake
Position a rack in the middle of the oven. Preheat the oven to 350°F (180°C/gas mark 4). Butter a 15-1/2-by-10-1/2-by-1-in (39-by-26.5-by-2.5-cm) jelly roll (Swiss roll) pan. Line the bottom with parchment (baking) paper and butter the paper.
Sift the flour, cocoa powder, baking soda (bicarbonate of soda), and salt into a medium bowl and set aside. In a large bowl, using an electric mixer on medium speed, beat the eggs and granulated sugar until thickened and lightened to a cream color, about 4 minutes. Stop the mixer and scrape the sides of the bowl as needed. Mix in the vanilla and almond extract (essence). Mix in half of the flour mixture just to incorporate it. Mix in the cream, then the remaining flour mixture, mixing just until the flour is incorporated and the batter looks smooth. Scrape the batter into the prepared pan and gently spread it so that it fills the pan evenly.
Bake until the top feels firm when gently touched and a toothpick inserted in the center comes out clean, about 15 minutes. Run a thin knife around the edges of the cake to loosen it from the pan. Cool the cake in the pan on a wire rack until it is cool to the touch, about 20 minutes. Spread a long sheet of wax (greaseproof) paper on the counter. Invert the cake onto the paper. Carefully peel off the parchment (baking) paper and discard it.
To Make the Filling and Frosting
Put the white chocolate in a heatproof bowl (or the top of a double boiler) and place it over, but not touching, barely simmering water in a saucepan (or the bottom of the double boiler). Stir constantly until the white chocolate is melted and smooth. Scrape into a large bowl and set aside to cool slightly.
In a large bowl, using an electric mixer on medium-high speed, beat the cream, powdered (icing) sugar, vanilla, almond extract (essence), and Amaretto until firm peaks form. Whisk about 1/2 cup (120 ml) of the whipped cream into the melted white chocolate until the white chocolate is blended into the cream. Use a rubber spatula to fold in the remaining whipped cream.
Use a large, sharp knife to cut the cake into four equal rectangles, each measuring about 7-1/2 by 5 in (19 by 12 cm). Use a large spatula to transfer one of the rectangles to a serving plate. Tuck wax (greaseproof) paper strips 1 in (2.5 cm) or so under the cake all the way around to keep the plate clean. Spread about 3/4 cup (180 ml) of the white chocolate whipped cream over the cake. Carefully place a cake rectangle on top of the filling and spread with whipped cream. Repeat the layers two more times. Spread the remaining white chocolate whipped cream over the top and sides of the cake.
Put the bittersweet chocolate in a heatproof bowl (or the top of a double boiler) and place it over, but not touching, barely simmering water in a saucepan (or the bottom of the double boiler). Stir constantly until the chocolate is melted and smooth. Spoon the melted chocolate into a medium pastry bag fitted with a small round tip with about a 1/8-in (3-mm) opening. Hold the pastry tip just above one end of the cake and pipe a series of curved, connected zigzagging lines over the top of the cake.
Use a long serrated knife to cut the cake, or cover and refrigerate the cake for up to 2 days. If refrigerated overnight, the cake is easier to cut and the flavor mellows as the white chocolate cream flavors the cake.