Recipe from The Tasty Tart Cookery School 

Preheat oven to 220°C, 425°F, Gas Mark 7 

To make the custard/pie filling: 
Start by cutting the pumpkin in half and clean out the seeds. Once clean, cut the pumpkin into small pieces. Place on a baking sheet and bake in oven for 30-45 minutes, or until soft. Let cool, then remove flesh from skin and puree or mash the flesh with the back of a fork. Leave the pulp in a fine meshed sieve for a minimum of 2 hours or leave overnight over a bowl to allow excess water to extract itself.
Meanwhile, make the pastry. 

For the Pastry:  
Directions 
In a bowl combine flour, salt, and sugar. Add butter, and quickly process by crumbling butter into the flour with your fingertips until the mixture resembles coarse breadcrumbs.Stir in water, a tablespoon at a time, until mixture forms a ball. Wrap in clingfilm and refrigerate for at least 1 hour or overnight.

Once puree is ready, mix all ingredients together until the mixture is smooth. Roll out pastry and place in a 9″ pie dish. Crimp the edges between your fingers. Place the custard inside the pastry. Bake at 230°C,450°F, Gas Mark 8 for 15 minutes; reduce heat to 180°C,350°F, Gas Mark 4 for 25 minutes more or until the tip of a sharp knife inserted comes out clean. Let cool for at least 10 minutes before serving. 

Serve with Chantilly whipped cream. 

Chantilly Whipped Cream: 
Whisk the cream, sugar, and vanilla in a large bowl until soft peaks form. The cream should hold its shape but still be satiny in appearance.