Freeze the hazelnut spread centres

• Cut cling wrap into small squares.
• Scoop Nutella and hazelnut spread onto individual squares.
• Fold to seal and freeze until solid.

Make the cookie dough

• In a large mixing bowl, whisk the cubed cold butter until slightly creamy.
• Add the caster sugar and light brown sugar and whisk until well combined and fluffy.
• Add the eggs and vanilla extract and whisk until fully incorporated.

Add the dry ingredients

• Add the flour, baking powder, baking soda and salt.
• Gently mix until just combined, without overmixing.

Stuff and shape the cookies

• Portion the dough into balls of about 65–70 g.
• Press a frozen Nutella hazelnut piece into the centre of each ball, seal well and roll into a smooth ball.

Freeze the dough balls

• Place the cookie dough balls on a tray and freeze.

Bake the cookies

• Preheat the oven to 175–180 °C.
• Bake until the tops are lightly golden while the centres remain soft.
• Remove from the oven and let cool.

Melt the chocolate coating

• Melt the milk chocolate using the double boiler method.
• Stir the chopped roasted hazelnuts into the melted chocolate.

Coat the cookies

• Spread a layer of the chocolate-hazelnut mixture onto baking paper, enough to coat the base of a cookie.
• Gently place the cooled cookie on top, then spoon more of the mixture over it so it is fully and evenly covered.

Set and serve

• Let the chocolate coating set completely before serving.