Preheat your oven to 350°F (175°C). Gently separate the kataifi strands and coat them with melted unsalted butter. Spread the kataifi mixture on a baking sheet lined with parchment paper and bake for 12-15 minutes until golden brown and crispy. Let cool.

In a microwave-safe bowl, melt the white chocolate in 30-second intervals, stirring to prevent burning. Mix in the natural pistachio butter and a pinch of salt until smooth. Add neutral vegetable oil if desired.

Finely chop the cooled kataifi and add to the pistachio mixture. Fold gently to combine, ensuring even distribution.

Scoop out portions of the mixture and form walnut-sized balls. Refrigerate for at least 30 minutes to firm up.

Melt the dark chocolate until smooth and glossy. Allow to cool slightly, ensuring it's pourable but not too hot.

Dip each ball into the melted dark chocolate, shaking off excess. Sprinkle with chopped pistachios while the chocolate is wet.

Arrange coated balls on a cooling rack or parchment-lined tray. Allow chocolate to set at room temperature for about 15 minutes, then store in an airtight container in the refrigerator for up to a week.