1-Getting Started: First, preheat your oven to 180°C (350°F) and line a baking sheet with parchment paper for even baking. This step helps the cake release easily later. Separate the eggs, beating the whites until stiff peaks form to create a light texture.

2-Mixing the Batter: Next, in another bowl, whisk the egg yolks with sugar until creamy. Gently fold in the sifted cake flour, unsweetened cocoa powder, baking powder, espresso powder, and salt. Be careful to keep the mixture airy by mixing lightly.

3-Baking and Rolling: Pour the batter evenly into the prepared tray and bake for 12-15 minutes until it springs back when touched. Once done, invert the cake onto a clean towel and peel off the parchment. Roll it up with the towel and let it cool to hold its shape.

4-Filling and Frosting: For the filling, whip the heavy cream with powdered sugar and vanilla extract until stiff peaks form. Unroll the cooled cake, spread the filling evenly, and roll it back up. Finally, prepare the chocolate ganache by melting the chopped bittersweet or dark chocolate with heavy cream, unsalted butter, vanilla extract, and a pinch of salt, then frost the outside and decorate.