Preheat the oven to 350 degrees F.
Add the pumpkin puree, eggs, egg yolk, maple syrup, almond milk, arrowroot, vanilla extract, pumpkin pie spice, ground cinnamon, and salt to a mixing bowl. Whisk all of the ingredients together until combined.
If using an aluminum pie tin, place inside a glass pie plate. (If you don't have a pie plates, you can also place the tin on a baking sheet). Alternatively, you can place the pie crust directly in a 9-inch pie plate. Pour the pumpkin pie filling into the crust.
Bake for 50-60 minutes or until a knife inserted into the centre comes out clean.
Remove the pie from the oven and allow it to cool on a wire rack. For best results, allow the pie to cool for at least 4 hours to firm up before cutting.
Serve at room temperature with a dollop of whipped cream and a sprinkle of cinnamon, if desired.