I have been developing this recipe for the last 3 years and this has become my final version, I have used this recipe for small batches all the way to catering and baking 100+ at a time.
Ingredients
Scale
Method
Soften butter by microwaving for 10sec intervals or leaving out for 10 minutes.
Cream with butter sugars and salt until mayonnaise-like consistency
Add Eggs, vanilla, and cocoa to butter mix until incorporated. Leave for a few minutes if you can so the cocoa can bloom.
Mix Dry ingredients (Flour and Baking soda) into wet ingredients. Add it in halves or thirds whichever is easier for you.
Add chocolate and half of the chopped hazelnuts into the dough.
Portion in 50g Balls chill in the fridge for 30 min (ideally overnight). For more flavor I recommend toasting the nuts a little bit.
preheat oven to 180C (356°F) while you roll the cookie dough balls in the remaining chopped hazelnuts.
Bake for 10 minutes or until edges of cookie begin to harden.
Notes
yes I add the cocoa powder with the wet ingredients as it helps it have a stronger chocolate flavour since it blooms to enhance flavours.