Pistachio and chocolate kataifi slice

Name: Pistachio and chocolate kataifi slice
Prep time: 30 min
Cook time: 12 h 45 min
Total time: 12 h 45 min
Yield: 16 slices
Ingredients: 60 g kataifi pastry; 50 g shelled unsalted pistachio nuts; 75 g white sugar; 2 eggs; 100 g butter; 150 g white chocolate; 80 g plain flour; 1 tsp baking powder; 300 g pistachio cream; 100 g dark chocolate; 80 g pouring (whipping) cream