Chocolate Pistachio Roll Cake

Chocolate Pistachio Roll Cake

This chocolate pistachio roll cake is a showstopper of a cake that tastes as good as it looks! It does take a bit of time to make, but it's not particularly difficult. The cake keeps well after assembly, too. Just keep it covered and stored in the refrigerator.

Ingredients :

• 1/3 cup finely ground unsalted pistachios
• 1/3 cup dutch-processed cocoa powder
• 1/4 cup all-purpose flour
• 1 teaspoon instant espresso powder (optional)
• 1/2 teaspoon baking soda
• 1/2 teaspoon baking powder
• 1/2 teaspoon salt
• 4 large eggs, separated, at room temperature
• 1/4 cup white sugar
• 1/8 teaspoon cream of tartar
• 1/3 cup light brown sugar
• 2 tablespoons unsalted butter, melted and slightly cooled
• 2 tablespoons brewed black coffee, at room temperature
• 1 teaspoon vanilla extract
• 1/2 teaspoon almond extract
• 2 tablespoons confectioner's sugar or cocoa powder, plus more as needed
• 8 ounces cold mascarpone cheese
• 1 tablespoon cold pistachio cream
• 1/4 cup confectioners sugar, or to taste
• 1 tablespoon tahini
• 1/4 teaspoon salt
• 1/4 teaspoon almond extract
• 1/4 teaspoon vanilla extract
• 2/3 cup cold heavy cream
• 4 ounces semisweet chocolate, chopped
• 1/2 cup heavy cream
• 1 tablespoon corn syrup

Directions

1. Preheat the oven to 350 degrees F (180 degrees C). Grease a rimmed 12x17-inch baking sheet and line the bottom with parchment paper; grease the parchment.
2. In a medium bowl, sift together ground pistachios, 1/3 cup cocoa powder, flour, espresso powder, baking soda, baking powder, and salt. Set aside.
3. Combine egg whites and cream of tartar in a large bowl. Beat with an electric mixer until soft peaks form. Gradually drizzle in white sugar, 1 tablespoon at a time, until incorporated. Keep beating mixture on medium-high speed until stiff, glossy peaks form, 3 to 5 minutes. Set aside.
4. In a second bowl, beat together egg yolks and brown sugar until thickened, about 2 minutes. Mix in butter, coffee, vanilla, and almond extracts until combined. Add in flour mixture and beat on low speed just until incorporated. Fold in about 1/3 of whipped egg whites until incorporated. Fold in remaining egg whites just until no streaks of white remain.
5. Pour batter into the prepared pan and smooth into an even layer. Tap pan on the counter a few times to pop any large air bubbles.
6. Bake in the preheated oven just until the cake springs back when lightly touched, 10 to 12 minutes.
7. Meanwhile, lay out a piece of parchment or a kitchen towel slightly larger than the cake pan. Generously dust the parchment or towel with 2 tablespoons confectioner’s sugar or cocoa powder.
8. Run a knife around the edges of the pan to loosen cake. Quickly and carefully invert cake onto the dusted parchment paper or kitchen towel, and carefully peel off and discard parchment from the bottom of the cake. Dust cake with a little more powdered sugar or cocoa powder. Starting from the shorter end, carefully roll cake up with the dusted parchment or kitchen towel. Place cake, seam-side down, on a wire cake to cool completely, about 1 hour.
9. For filling, add mascarpone, pistachio cream, powdered sugar, tahini, salt, almond extract, and vanilla to a bowl and beat with an electric mixer until smooth and combined. Add in heavy cream and beat on medium-high speed until mixture holds stiff peaks, about 3 minutes. Refrigerate filling until needed.
10. Carefully unroll cooled cake, and spread evenly with filling. You can reserve a small amount of filling to pipe on top of the cake just before serving (optional). Carefully roll cake back up, without parchment or towel, over the filling. Using a pastry brush, gently brush away excess powdered sugar or cocoa powder from the outside of the cake. Place cake onto a plate or platter and refrigerate for at least 1 hour.
11. For ganache, place chocolate, heavy cream, and corn syrup into a microwave-safe bowl. Heat in 30 second intervals, stirring after each, until chocolate is melted, and becomes smooth and combined, 1 to 2 minutes.
12. Remove cake from the refrigerator. Pour ganache over the cake. If desired, spoon any drippings back over cake and use an offset spatula or butterknife to help coat the cake fully. Refrigerate cake until ganache is set, about 30 minutes.
13. To serve the cake, carefully slice any uneven ends off to expose the spiral. If desired, pipe reserved filling over the top of the cake and garnish with a sprinkle of chopped pistachios. Store cake in the refrigerator.