In a large bowl combine all ingredients. Using a wooden spoon start mixing until you make a crumbly dough. Transfer the dough to a 8 -10 inch glass or porcelain pie dish.
Using your hands distribute the dough around the baking dish. Make a thin sheet and press it to the bottom and the sides of the dish.
Place the pan in the fridge while preparing the filling.
In a large mixing bowl combine all ingredients. Using an electric mixer beat for 1-2 minutes, until smooth and uniform.
Pour the filling into the prepared crust. Bake for 30- 40 minutes at 350 degrees F / 180 degrees C or until the filling starts becoming golden brown around the sides and on the top.
Let the pie cool completely at a room temperature. Cover with cling film and refrigerate it for at least 4 hours.
Serve with sweetened whipped cream or just plain.
To make the pumpkin puree: halve one pumpkin, clean the seeds and strings and place both halves on a large baking tin lined with sheet of parchment paper. You can place it with the peel down or up, however I find the first option better as that way you avoid all the water from the pumpkins leaking around the pan. Bake for 30-40 minutes or until soft (test with a fork). Let the pumpkin cool completely and then discard the peel and all burned parts. Puree the pumpkin in a food processor until smooth. Keep the pumpkin puree for up to 3 days refrigerated in an airtight container.
This pie is equally nice with pumpkin or butternut squash puree.