Preheat the oven to 180 degrees Celsius (350 degrees Fahrenheit).

Roll out the puff pastry and place it in a pie pan.

Prick the base of the pastry with a fork to prevent it from puffing up too much.

Drain the canned white beans and rinse them under running water.

Puree the rinsed white beans in a blender until smooth.

In a large bowl, combine the pureed white beans, sugar, flour, margarine, eggs, and grated coconut.

Beat the mixture well until it is completely homogenous.

Pour the batter into the prepared pie crust.

Sprinkle the top of the pie with sugar.

Bake for approximately 35 minutes, or until the crust is golden brown and the filling is set.

Let the pie cool slightly before dusting with powdered sugar and serving.