Step 1: Prepare the Kataifi Dough

1. Combine Dry Ingredients: In a mixing bowl, combine 180 g of all-purpose flour, 100 g of cornstarch, and ½ tsp of salt. Mix well.
2. Add Water and Oil: Gradually add 380 g of water and 25 g of vegetable oil to the dry ingredients, stirring until you have a smooth batter.
3. Cook the Mixture: Transfer the batter to a non-stick saucepan over medium heat. Cook, stirring continuously, until the mixture thickens to a paste-like consistency (about 10-15 minutes). It should pull away from the sides of the pan. Remove from heat and let cool completely.

Step 2: Prepare the Pistachio Filling

1. Melt the Butter: In a small bowl, melt 30 g of unsalted butter.
2. Mix the Fillings: In a separate bowl, combine 80-90 g of pistachio paste and 50 g of tahini paste. Add the melted butter and mix until smooth. If desired, add 1 tbsp of powdered sugar to sweeten the filling slightly. Mix well until fully incorporated.
3. Set Aside: Keep the pistachio filling aside while you prepare the kataifi.

Step 3: Assemble the Pastry

1. Prepare the Kataifi Dough: If using store-bought kataifi, gently unravel the strands. If you’ve made your own dough, use a pastry cutter to shred it into thin strands.
2. Grease the Baking Dish: Preheat the oven to 180°C (350°F). Grease a baking dish with a little melted butter.
3. Layer the Kataifi: Spread half of the kataifi dough in an even layer at the bottom of the greased baking dish.
4. Add Filling: Spoon the pistachio filling over the kataifi layer, spreading it evenly.
5. Top with Remaining Kataifi: Cover the filling with the remaining kataifi dough, pressing down gently to compact it.
6. Bake: Bake in the preheated oven for about 25-30 minutes or until golden brown.

Step 4: Prepare the Chocolate Coating

1. Melt the Chocolate: While the kataifi is baking, melt 300 g of milk chocolate in a heatproof bowl over simmering water or in the microwave in short bursts, stirring until smooth.
2. Temper the Chocolate: If using, add 3 g of cocoa butter powder to the melted chocolate to help temper it, which will give a shiny finish to the coating.

Step 5: Coat and Decorate the Pastry

1. Cool the Pastry: Once the kataifi is baked, let it cool slightly in the baking dish.
2. Cut into Pieces: Carefully cut the kataifi into squares or diamond shapes.
3. Dip in Chocolate: Dip each piece into the melted chocolate, ensuring they are well coated. Allow the excess chocolate to drip off.
4. Add Decorations: Drizzle with melted white chocolate and sprinkle with gold luster dust and green food coloring for a festive touch.

Step 6: Chill and Serve

1. Chill: Place the chocolate-coated kataifi in the refrigerator to set for about 30 minutes.
2. Serve: Once set, serve the kataifi pastries on a decorative plate. Enjoy with a cup of tea or coffee!