Place the butter in a large bowl or the bowl of a stand mixer and beat for around 40 seconds until the butter has softened into one large lump. Add the two sugars and beat again for the same amount of time. Add the chocolate and hazelnuts and beat until just combined.
In a separate bowl, mix together the flours, salt, baking powder and bicarbonate of soda then pour into the cookie dough mix. Beat for around 40 seconds until the mix appears sandy. Pour in the beaten eggs and combine to a soft dough that doesn’t stick to the sides of the bowl.
Press together balls of cookie dough around 125g in weight to make around a dozen cookies. Place the cookies into the freezer for at least 90 minutes or ideally overnight to rest before baking.
When you’re ready to bake your cookies, preheat the oven to 200oc/180oc fan and place a baking sheet lined with baking parchment in the oven while it heats up. Once the oven is up to temperature, place the cookie dough balls onto the hot tray straight from the freezer, which will help crisp up the bottoms. Space them well apart and bake for around 17 minutes until golden.
Remove from the oven and leave to cool on the tray for five minutes before transferring to a wire rack to cool a little. You can repeat with the rest of the cookie dough or keep in the freezer for a rainy day. Cookies will keep in an airtight container for up to five days.
Recipe by Victoria Sponge Pease Pudding at http://victoriaspongepeasepudding.com/baking/nyc-style-milk-chocolate-and-hazelnut-cookies/