To prepare the moulds
Brush six dariole moulds with melted butter.
Chill in the fridge for 10 minutes.
Brush again with melted butter and dust with cocoa powder.
Tap out any excess and set aside.

Making the ganache
Add chocolate into a medium bowl and set aside.
Add whipping cream into a heatproof bowl.
Heat in a microwave until boiling.
Pour the hot cream over chocolate.
Let rest for 1 minute.
Add hazelnuts.
Mix until combined and set aside to firm up.

Making the fondants
Preheat the oven to 180ºC.
Fit the Creaming Beater.
Add butter and dark chocolate into the Warming bowl, fit the splashguard.
Heat for 10 minutes on heat setting 7, speed Stir 1, until melted.
Set the bowl aside and let cool slightly.
Add egg whites into the 5L Appliance bowl.
Remove the Creaming Beater and fit the Whisk Tool.
Whisk for 1 minute on speed Max.
Add sugar while the machine is running.
Whisk for 4 minutes on speed Max, until light and fluffy.
Add egg yolks and hazelnut spread to the melted chocolate and mix until combined.
Fold in the egg whites until combined.

Place the dariole moulds on a baking tray.
Fill the moulds with the fondant mixture until one third full.
Carefully spoon 1 tsp of hazelnut ganache into the centre of each mould.
Fill the moulds with the fondant mixture until two thirds full.
Tip: Leave a third of space to allow the fondants to rise.
Bake for 11-12 minutes at 180ºC, until risen and firm to touch.
Turn onto a plate and sprinkle with cocoa powder and hazelnuts.

Serve.