Preheat oven to 400oF (200oC).
To a bowl, add flour, sugar and salt. MixThen add oil and water. Mix until crumbly. Transfer dough to pan.
Distribute dough evenly and press across bottom and up the sides of the pan.
Use your fingers to crimp the edge.
Then, use the tines of a fork to pierce the bottom of crust.
Bake in preheated oven to 400oF (200oC), rack middle position, 18-20 minutes or until the edges are lightly golden brown. Remove from the oven and let cool completely before adding filling.
In the meantime, make the filling.
To a bowl, add corn starch, water, sugar and oil. Mix well.Then add pumpkin puree, cinnamon, salt, ginger and vanilla extract. Mix well. Transfer filling onto pie crust. Spread evenly using a spatula.
Bake in preheated oven to 350oF (180oC), rack middle position, 20 minutes or until the center is almost set.
Transfer the pie to a wire rack and allow to cool completely before serving.