Makes abut 36 cookies
375g plain flour
½ tsp salt
½ tsp baking powder
225g lightly salted butter, softened
2 large eggs
1 tsp vanilla extract
60g unsweetened cocoa
Whisk the sifted flour, salt and baking powder in a bowl and set aside.
Mix the butter, sugar, eggs, vanilla and cocoa in a mixer. Gradually add the flour mixture, and mix until smooth. Wrap in cling film and chill in the fridge for at least one hour or overnight.
Preheat oven at 175 ºC. Roll out the cookie dough on a floured counter. Cut the cookies out and brush extra deposits of flour off the top (although the flour will disappear once baked). Work quickly as the dough becomes sticky as it warms up.
Bake the cookies on a parchment-lined baking sheet for 8 to 11 minutes (depending how thick your cookies are) until the edges are firm and the centers are slightly soft and puffed.
Transfer to a wire rack to cool.