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Hot Cocoa Cake

By America's Test Kitchen

Published on October 5, 2014

Time

1 hour, plus 1½ hours chilling

Yield

Serves 12 to 16

Hot Cocoa Cake

Ingredients

1 teaspoon plain gelatin ¼ cup cold water 6 tablespoons unsalted butter, softened1 teaspoon vanilla extract Pinch salt 2 cups marshmallow crème 1 ½ cups heavy cream 3 tablespoons Dutch-processed cocoa powder, plus extra for dusting½ cup white chocolate chips 3 (8-inch) baked chocolate cake rounds 24-36 large marshmallows

Before You Begin

We like to use our Chocolate Layer Cake for this recipe.

Instructions

    for the filling

  1. Sprinkle gelatin over water in large bowl and let sit until softened, about 5 minutes. Microwave mixture until bubbling around edges and gelatin dissolves, about 30 seconds. Stir in butter, vanilla, and salt until combined. Let mixture cool until just warm to touch, about 5 minutes. Whisk in marshmallow crème until smooth; refrigerate marshmallow filling until firm enough to spread, about 1½ hours.
  2. for the frosting

  3. Bring 1/2 cup cream and cocoa to simmer in small saucepan over medium-high heat, whisking until smooth. Pour cream mixture over white chocolate chips in small bowl and whisk until melted and smooth. Let white chocolate mixture cool completely, about 30 minutes. Using stand mixer fitted with whisk, whip remaining 1 cup cream with cooled white chocolate mixture on medium-high speed until soft peaks form, 60 to 90 seconds.
  4. to assemble

  5. Place 1 cake layer on plate or pedestal. Spread half of filling in even layer over top. Top with second cake layer and remaining filling. Place third cake layer on top. Spread top and sides of cake with even layer of frosting. Arrange marshmallows on top in large mound; dust with extra cocoa. Serve.
Hot Cocoa Cake

Hot Cocoa Cake

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By America's Test Kitchen
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Time

1 hour, plus 1½ hours chilling

Yield

Serves 12 to 16

Ingredients

Ingredients

Ingredients

Why This Recipe Works

UPDATE: This recipe has been slightly reformulated to be more foolproof since its initial publication. The revision you see here was published in May of 2020. Reminiscent of a steaming hot mug of cocoa on a cold winter morning, this rich layer cake gets its name from the combination of chocolate cake and marshmallow filling. To make the filling, we stabilize marshmallow crème with gelatin and then stir in butter and vanilla for creaminess and flavor. For the frosting, we use a combination of cocoa powder and white chocolate chips added to fresh whipped cream. The top of the cake (like the top of your hot chocolate) gets a garnish of marshmallows and a dusting of cocoa.

Before You Begin

We like to use our Chocolate Layer Cake for this recipe.

Instructions

    for the filling

  1. Sprinkle gelatin over water in large bowl and let sit until softened, about 5 minutes. Microwave mixture until bubbling around edges and gelatin dissolves, about 30 seconds. Stir in butter, vanilla, and salt until combined. Let mixture cool until just warm to touch, about 5 minutes. Whisk in marshmallow crème until smooth; refrigerate marshmallow filling until firm enough to spread, about 1½ hours.
  2. for the frosting

  3. Bring 1/2 cup cream and cocoa to simmer in small saucepan over medium-high heat, whisking until smooth. Pour cream mixture over white chocolate chips in small bowl and whisk until melted and smooth. Let white chocolate mixture cool completely, about 30 minutes. Using stand mixer fitted with whisk, whip remaining 1 cup cream with cooled white chocolate mixture on medium-high speed until soft peaks form, 60 to 90 seconds.
  4. to assemble

  5. Place 1 cake layer on plate or pedestal. Spread half of filling in even layer over top. Top with second cake layer and remaining filling. Place third cake layer on top. Spread top and sides of cake with even layer of frosting. Arrange marshmallows on top in large mound; dust with extra cocoa. Serve.
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