Preheat your oven to 375°F (190°C) and line a rimmed baking sheet with parchment paper.

In a large mixing bowl, separate the egg whites from the yolks and whip the whites until stiff peaks form (3-5 minutes).

In another bowl, whisk together the yolks, sugar, and vanilla extract until pale and creamy (2-3 minutes). Then gently fold it into the whipped egg whites.

Sift the flour, cocoa powder, baking powder, and salt into the mixture and fold gently until just combined.

Pour the batter onto the prepared baking sheet and bake for 12-15 minutes until golden and springy.

Once baked, loosen edges and flip onto a kitchen towel dusted with powdered sugar. Roll the cake while warm to prevent cracking.

Allow the rolled cake to cool completely on a wire rack.

Whip heavy cream until soft peaks form, add vanilla and continue whipping until fluffy.

Carefully unroll the cooled cake, spread the whipped cream filling, and re-roll without the towel.

Wrap in plastic wrap and chill in the fridge for at least 1 hour before slicing.