Preheat your oven to 180°C (350°F). Line two baking trays with parchment paper.

In a frying pan, melt butter over medium heat. Add kataifi pastry and toast for about 10 minutes until golden brown.

In a stand mixer, combine cold unsalted butter, light brown sugar, superfine sugar, and vanilla extract. Beat for about 4 minutes until fluffy.

In a separate bowl, whisk together cake flour, baking powder, and salt. Gradually add this to the creamed butter mixture and mix until just combined.

Fold in the chocolate chips, chilling the dough if necessary to maintain shape.

In a bowl, mix cooled toasted kataifi, pistachio paste, tahini, and a pinch of salt until smooth.

Divide cookie dough into portions, flatten slightly, place pistachio filling in center, seal and roll into a ball.

Arrange cookies on baking trays, bake for 20-22 minutes or until edges are golden and centers are soft.

Cool cookies on trays for about 20 minutes, drizzle with melted chocolate and top with toasted kataifi and pistachios.