For the filling -
1. To a pan, melt butter then add the katifi pastry. Continue to mix until toasted and the pastry starts going brown.
2. Transfer the katifi to a bowl and add the pistachio cream, mix until well combined.
3. Scoop approx 1 Tablespoon-sized balls onto a small baking sheet lined with baking paper. Transfer to freezer to freeze while you prepare the cookie dough.

For the cookie dough -
1. Melt butter in a large, microwave-safe bowl. Add cocoa powder and oil and stir well. Allow it to cool slightly before proceeding to the next step. 

2. Once butter mixture is cooled, add sugars, eggs, and vanilla extract and stir well.
3. In a separate, medium-sized mixing bowl, whisk together flour, cornstarch, baking soda, baking powder, and salt.
Once well-combined, gradually add to the butter mixture, stirring until completely combined.

4. Weigh the cookie dough into 100g balls and roughly roll them into balls. Using your thumb, form and indent in the centre or the dough and place a ball of pistachio filling in the centre. Then wrap the dough around it to cover it and roll the ball in your hands ensuring all sides are smooth and the filling is completely covered.
5. Place cookie dough balls in the freezer for 3 hours minimum.
6. When ready to bake, preheat oven to 175C. Remove the cookie dough balls from the freezer and place on trays with baking paper ensure to space them apart.
7. Bake for 10-13 minutes.

Allow to cool completely (approx 10mins) then add optional topping of a drizzle of melted choc & crushed pistachios