Preheat the oven to 220°C / 425°F / Gas Mark 7. Line a baking tray with parchment paper.
Combine the butter and sugar together in a small bowl using a hand held blender until it is fluffy.
Beat the egg whites together in a jug.
Spoon the flour into the butter mix and pour in the egg whites.
Mix together and add the melted chocolate and vanilla extract.
When the batter is well combined use a tbsp to scoop out the mixture onto the prepared baking tray. Spread it around into an oval shape.
You will only get be able to make about 4 or 5 at a time.
Place it in the oven for about 2/3 minutes until golden.
Remove from oven and quickly roll into a tube before it cools. Pipe the Nutella into the centre of the roll and allow to set.
Do this until all the batter is used up.