Make or buy a vegan pastry crust and form it into a 9-inch pie dish.
Bake the pie crust for 10 minutes.
While the crust is baking, add the pumpkin, coconut milk, brown sugar, chickpea flour, pie spice, vanilla, and salt to the blender and blend for about 30 seconds.
Pour the filling into the cooked pie crust that has been baked for 10 minutes.
Bake the pie at 350°F (177°C) for 1 hour and 15 minutes. (The top of the pie should look slightly dry, and there may be small cracks at the sides of the pie.
Allow to cool at room temperature for 1 hour, then refrigerate for at least 3 more hours before cutting. It will be best if it is left in the refrigerator overnight.
Notes
Pour the pie filling into the pie shell near the oven so you don't have to walk far with it. It will be very runny and easy to spill.
Don't cook hotter than 350°F (177°C). This pie needs to cook long and slow to ensure it cooks through completely.
Make sure to cook the pie for the full 75 minutes. Remember, the chickpea flour tastes awful if it is not thoroughly cooked through.
Store in the fridge uncovered until fully cooled. Don't cover until all the steam has left the pie.
It is best after it has cooled overnight in the fridge. (It's still delicious the first day, but just firmer and denser once it has chilled).