6. Pour the white half of the batter onto a parchment-covered baking sheet, and spread evenly.
7. Bake for 5 minutes at 190°C/375°F.
8. Pour the chocolate batter on top of the base layer and spread it out evenly. Bake for 8 minutes.
9. Let the roll cool down, peel the parchment back, and spread hazelnut cream on top of the cake base. Roll tightly and leave in the fridge to set.
10. Carefully slice the roll and dip each slice in melted chocolate, covering one side.
