Sauté the grated pumpkin with the sugar over medium heat for 12–15 minutes, until most of the juices have evaporated. Stir occasionally, but don’t turn it into a mash.
Add the walnuts, dried fruit and vanilla extract, then set aside to cool.
When you are ready to bake, preheat the oven to 200°C.
Unroll the puff pastry and, keeping the long side parallel to you, spread the pumpkin filling over half of it from left to right.
Fold the other half over the filling, seal the edges by pressing them with your hands or a fork, and brush it with egg wash.
Transfer it to a lined baking sheet large enough to accommodate the pie.
Bake for 18 minutes or until golden on the middle rack.
Remove from the oven and allow it to cool.
Dust with icing sugar or pumpkin spice icing sugar.