Preheat the oven to 200°C (400°F).
Roll out the puff pastry sheets on a lightly floured surface.
Cut one sheet into a Christmas tree shape.
Place the tree shape on a baking sheet lined with parchment paper.
Layer the cranberry sauce and Camembert on the pastry.
Sprinkle the chopped pistachios over the filling.
Use the second sheet of pastry to cover the filling, sealing it at the edges.
Brush the top with beaten egg.
Cut small slits in the pastry to resemble tree branches.
Bake in the preheated oven for 20-25 minutes.
Remove from the oven and let cool slightly before serving.
