Toast the nuts in a dry pan until fragrant, then let them cool. Chop half of the nuts and leave the other half whole.

Cream the softened butter and powdered sugar together until smooth. Add the egg yolk and mix well.

Sift in the cake flour, almond flour, and cocoa powder. Gently fold the mixture until no dry flour is visible.

Add the chopped nuts and chocolate chips to the dough and mix until evenly distributed.

Add the milk and mix until the dough comes together.

Shape the dough into a log, wrap it, and chill in the freezer for 1 hour.

Roll the chilled dough in sugar and slice into 1.5cm thick rounds.