1. Beat the yolks with half the sugar.
2. Add the vanilla essence and melted butter.
3. Add the sifted dry substances and blend.
4. Beat the egg whites till stiff with the remainder of the sugar and add this combination to the earlier preparation, little by little and with enveloping actions.
5. Cowl a 30 x 45 cm aspect plate with buttered parchment paper and distribute the preparation forming a skinny layer.
6. Cook dinner in a preheated oven at medium temperature (180º C) for roughly 10 minutes.
7. Unmold sizzling on a bit of parchment paper sprinkled with bitter cocoa. Roll up and let cool.
8. For the filling, beat the cream with the powdered sugar and the vanilla essence till whipped.
9. Unroll, fill with the cream and roll. Let cool nicely.
10. To cowl, soften the chocolate with the butter in a bain-marie or within the microwave and canopy the roll.
