Cream the softened unsalted butter with powdered sugar, fine salt, and vanilla extract until pale and fluffy.

Gradually sift in half of the all-purpose flour and Dutch processed cocoa powder, mixing until combined, then add remaining flour and cocoa.

If the dough feels too soft, wrap in plastic wrap and refrigerate for about 30 minutes.

Preheat the oven to 150°C (300°F) and prepare a baking tray lined with parchment paper.

Once the dough has chilled, press it flat in the lined baking tin and bake for 20 minutes, cut into bars while warm and bake for another 20 minutes.

Alternatively, shape the dough into a log, chill, and slice into rounds before baking.

Roll out the dough for fun shapes using cookie cutters and bake for about 20 minutes.

Melt dark cooking chocolate and vegetable oil, dip the biscuits, and let set on a tray.