Heat 2 tablespoons butter in a skillet over medium heat. Add the kataifi pastry and cook slowly while stirring until golden and crispy. Set aside to cool slightly.
In a large bowl combine the grated pumpkin, brown sugar, cinnamon, nutmeg, vanilla, and melted butter until evenly mixed.
In a separate bowl combine the pistachio cream, toasted kataifi, and chopped pistachios.
Lay one filo sheet on a clean surface and brush lightly with melted butter. Add another filo sheet on top.
Spread pumpkin filling across the lower half of the filo. Add spoonfuls of the pistachio mixture and sprinkle chopped chocolate over the filling.
Roll tightly into a log. Repeat with remaining ingredients.
Arrange the rolls into a spiral shape inside a buttered baking pan or place side by side.
Brush generously with melted butter.
Bake at 375°F for 40–45 minutes or until deeply golden and crispy.
Allow the tikvenik to cool slightly before slicing.
Drizzle with melted chocolate and top with crushed pistachios before serving.
