Preheat your oven to 180°C (350°F) and line a baking tray with parchment paper.

In a large bowl, whisk the eggs and sugar until pale and fluffy.

Sift the flour, cocoa powder (if using), and salt together.

Gently fold the dry ingredients into the egg mixture.

Add the vanilla extract and mix until combined.

Pour the batter into the prepared tray and spread evenly.

Bake for 12-15 minutes or until the cake springs back when touched.

Remove from the oven and let it cool for a few minutes.

Turn the cake onto a clean kitchen towel dusted with powdered sugar.

Spread the filling of your choice evenly over the cake, then roll it tightly using the towel.