Preheat the oven to 350 degrees F (175 degrees C). Spread the kataifi on a 10x15-inch rimmed baking sheet, toasting it while stirring halfway through, for about 10 to 12 minutes until golden. Let it cool for 15 minutes.

In a bowl, stir together 3/4 cup of the toasted kataifi, graham cracker crumbs, finely chopped pistachios, melted butter, and sugar. Press this mixture into the bottom of a 9-inch springform pan, then bake for 12 to 15 minutes until golden. Reduce the oven temperature to 325 degrees F (163 degrees C).

Whisk together 1 cup of heavy whipping cream, 1 cup of pistachio cream, and tahini in a bowl until smooth.

In another bowl, combine the white chocolate chips with 1/3 cup of heavy whipping cream. Microwave on High, stirring every 30 seconds until melted, about 1 to 2 minutes. Let cool.

In a large mixing bowl, beat cream cheese and sugar with an electric mixer at medium speed until smooth. Add eggs one at a time, mixing well after each addition. Mix in the cooled white chocolate mixture and vanilla extract until combined.

Pour half of the cream cheese mixture into the crust, topped with the pistachio cream mixture. Pour the remaining cream cheese mixture on top and swirl together slightly for a marbled effect.

Bake in the preheated oven for 55 to 60 minutes until set around the edges. Turn off the oven and leave the door ajar for about an hour to cool. Cover and chill in the pan overnight.

Stir together the remaining pistachio cream, tahini, and kataifi. Spread over the cheesecake.

Microwave milk chocolate and whipping cream until melted, about 1 to 2 minutes. Pour over the cheesecake, chilling once more, covered, for at least an hour before serving.