Name: Chocolate-Raspberry Heart Cake
Total time: 3 h
Ingredients: 7 1/2 ounces (213 grams/1½ cups) fresh or thawed frozen raspberries , plus about 20 fresh raspberries; 8 ounces (227 grams) white chocolate , melted and cooled slightly; 1 1/2 cups (10 1/2 ounces/298 grams) sugar; 6 large egg whites; 1/8 teaspoon salt; 24 tablespoons (3 sticks) unsalted butter , cut into 24 pieces and softened; 1¼ cups (6¼ ounces/177 grams) all-purpose flour; ¾ cup (2¼ ounces/64 grams) unsweetened cocoa powder; ½ teaspoon baking soda; ¼ teaspoon salt; 8 ounces (227 grams) semisweet chocolate , chopped; 12 tablespoons unsalted butter; 1½ cups (10½ ounces/298 grams) sugar; 1 cup buttermilk; 4 large eggs; 1 teaspoon vanilla extract

Chocolate-Raspberry Heart Cake

By America's Test Kitchen

Published on January 4, 2016

Time

2 hours, plus 1 hour cooling

Yield

Serves 14-16

Ingredients

Frosting

7 ½ ounces (213 grams/1½ cups) fresh or thawed frozen raspberries, plus about 20 fresh raspberries8 ounces (227 grams) white chocolate, melted and cooled slightly1 ½ cups (10 ½ ounces/298 grams) sugar 6 large egg whites ⅛ teaspoon salt 24 tablespoons (3 sticks) unsalted butter, cut into 24 pieces and softened

Cake

1¼ cups (6¼ ounces/177 grams) all-purpose flour ¾ cup (2¼ ounces/64 grams) unsweetened cocoa powder ½ teaspoon baking soda ¼ teaspoon salt 8 ounces (227 grams) semisweet chocolate, chopped12 tablespoons unsalted butter 1½ cups (10½ ounces/298 grams) sugar 1 cup buttermilk 4 large eggs 1 teaspoon vanilla extract

Instructions

for the cake

Adjust oven rack to middle position and heat oven to 325 degrees. Grease 8-inch square baking pan and 8-inch round cake pan, line each with parchment paper, grease parchment, and flour pans.

Sift flour, cocoa, baking soda, and salt together in bowl. Microwave chocolate and butter in second bowl at 50 percent power, stirring occasionally, until melted, 2 to 4 minutes. Whisk sugar, buttermilk, eggs, and vanilla together in third large bowl.

Whisk chocolate mixture into sugar mixture until combined. Whisk in flour mixture until smooth. Divide batter evenly between prepared pans and bake until toothpick inserted in center of each cake comes out clean, 35 to 45 minutes, switching and rotating pans halfway through baking. Let cakes cool in pans on wire rack for 10 minutes. Run thin knife around edge of pans, remove cakes from pans, discarding parchment, and let cool completely on rack, about 1 hour.

for the frosting

Process 1½ cups raspberries in food processor until smooth, about 30 seconds. Strain puree through fine-mesh strainer into bowl; discard solids and set aside puree. Microwave chocolate in bowl at 50 percent power, stirring occasionally, until melted and smooth, 1 to 2 minutes; let cool slightly. Combine sugar, egg whites, and salt in bowl of stand mixer. Set bowl over saucepan filled with 1 inch barely simmering water, making sure that water does not touch bottom of bowl. Cook, whisking constantly, until mixture reaches 160 degrees, 5 to 8 minutes. Remove bowl from heat and transfer to stand mixer fitted with whisk attachment. Whip warm egg mixture on medium-high speed until stiff peaks form, about 5 minutes. Reduce speed to medium-low and add butter, 1 piece at a time, and whip until smooth and creamy, about 2 minutes. Add chocolate and mix until just combined. Slowly add raspberry puree and mix until incorporated.

Place 1 corner of square cake against lower edge of large (about 16-inch diameter) cake plate or pedestal. Using serrated knife, shave domed top from round cake to make it level with square cake; discard top. Cut round cake in half. Place halves, with cut sides facing in, against top 2 edges of square cake to form heart shape. Spread 2½ cups frosting over top and sides of cake in thin, even layer. Fill pastry bag fitted with star tip with remaining frosting and pipe roses (spiraling from inside out) over top and sides of cake. Place fresh raspberries between roses. Serve.