This towering cake melds rich bittersweet ganache, creamy milk-chocolate mousse, and multiple layers of chocolate sponge cake. Adorned with buttery brittle, it can't help but set hearts aflutter.

Martha Stewart Living, February 2008




For the cake
For the cashew brittle
For the mousse
For the ganache
For the syrup
For garnish


Instructions Checklist
  • Make cake: Preheat oven to 350 degrees. Butter an 8-inch round cake pan. Line with parchment, and butter parchment. Sift together flour, cocoa, and salt.

  • With a mixer fitted with the whisk attachment, beat egg yolks and sugar on medium-high speed until pale and thick, about 7 minutes. Beat in vanilla.

  • With a mixer fitted with the whisk attachment, beat egg whites until medium-stiff peaks form. Fold into yolk mixture in 3 additions. Fold in flour mixture in 2 additions until almost incorporated. Fold in butter. Pour into pan.

  • Bake cake until a toothpick inserted into center comes out clean, 25 to 30 minutes. Let cool completely in pan on a wire rack. Invert onto rack. Remove parchment, and turn right side up.

  • Make brittle: Bring sugar, corn syrup, water, and salt to a boil, stirring until sugar has dissolved. Wash down sides of pan with a wet pastry brush, and cook until pale amber, about 12 minutes total. Stir in butter. Remove from heat, and stir in cashews. Pour onto a parchment-lined baking sheet to cool. Coarsely chop.

  • Make mousse: Melt chocolates and butter in a heatproof bowl set over simmering water, stirring occasionally. Cool 20 minutes. Keep water simmering.

  • Combine yolks, sugar, and salt in a heatproof bowl set over simmering water. Whisk until sugar has dissolved and mixture reaches 160 degrees on a candy thermometer. Remove from heat. With a mixer fitted with the whisk attachment, beat on medium-high speed until thick and cool, about 7 minutes.

  • Whisk cream, creme fraiche, and vanilla until medium-stiff peaks form. Fold chocolate mixture into yolks. Fold in cream mixture, and then 1 1/2 cups brittle. Cover, and refrigerate, stirring occasionally, until slightly thickened, 1 hour.

  • Make ganache: Fill a bowl halfway with ice water, and set aside. Combine chocolates and salt in a heatproof bowl. Bring milk, cream, and butter to a boil. Pour over chocolate, and whisk until smooth. Reserve 1 cup ganache at room temperature. Place bowl with remaining ganache in ice water, and whisk constantly, scraping bowl, until ganache is set but not solid.

  • Make syrup: Mix liqueur and vanilla.

  • Assemble cake: Using a serrated knife, trim rounded top of cake to create a flat surface, and shave off just the slightest bit of cake around edges so that it fits inside an 8-by-3-inch springform pan without touching sides. Cut cake in half horizontally. Cut both layers in half horizontally to make 4 layers. Place 1 layer in pan. Brush with 1/4 of the syrup. Top with 1/2 cup ganache and 1 cup mousse. Repeat with cake, syrup, ganache, and mousse. Spread 1 cup reserved ganache over top. Refrigerate at least 2 hours (preferably overnight).

  • Run an offset spatula around edges of pan, and remove sides. Garnish with berries and, if desired, Cashew-Brittle Hearts.