Weigh out the ingredients
I
You'll need flour, sugar, cocoa powder, chocolate, vanilla, espresso powder, salt, oil, and eggs.
Weigh out the ingredients
II
For the filling and ganache, you'll need heavy cream, mascarpone, sugar, and chocolate.
In a small heat-proof bowl, combine the chocolate, oil, vanilla, espresso powder, and salt. Place the bowl over a small pot of simmering water, and stir frequently until the chocolate has full melted. Set aside to cool.
Melt the chocolate
III
In the bowl of a stand mixer fitted with the whisk attachment, beat the egg yolks and sugar on high speed until doubled in size and the mixture drizzles off the whisk like a ribbon.
Beat egg yolks & sugar
IV
Pour the cooled chocolate mixture into the egg yolk mixture and mix to combine.
Mix in the chocolate mixture
V
In a separate bowl, add the egg whites and use an electric hand mixer to beat until stiff peaks form.
Beat the egg whites
VI
Use a rubber spatula to fold ⅓ of the egg whites into the yolk, chocolate mixture to loosen it up, then fold in the rest until fully combined.
Fold egg whites into batter
VII
Sift the flour and cocoa powder on top of the batter, then gently fold it in until fully combined. Be careful not to deflate those egg whites!
Fold in dry ingredients
VIII
Pour the cake batter into the prepared jelly roll pan. Bake the chocolate sponge for about 13-15 minutes or until a toothpick inserted comes out clean. Do not over-bake!
Bake
IX
Immediately turn the cake out onto the parchment paper greased with butter. Carefully roll the cake up into a loose swirl. Place in the fridge to chill for 20-30 minutes.
Roll & cool
X
In a medium bowl, add the mascarpone and sugar. Use an electric mixer to beat on low-medium speed until smooth. Then, add the heavy cream and continue beating until stiff peaks form.
Make the cream filling
XI
In a small saucepan, heat the heavy cream over low heat and bring to a simmer. Pour the heavy cream over the chocolate, and allow to sit for a couple minutes. Gently stir with a rubber spatula until the ganache is smooth. Alternatively, you can use an immersion blender.
Make the ganache
XII
Over a wire rack, very slowly unroll the cake half way. Spread the mascarpone cream on the inside of the cake, coaxing it up to the center part of the swirl. Roll the cake back up and remove the parchment paper. Pour the ganache over the cake, then transfer to a serving plate.
Assemble
XIII
Slice the cake and enjoy!
Enjoy!
XIV