Step 1: Prepare the Pie Crust

1. Mix flour, sugar, and salt in a bowl.
2. Cut in cold butter until the mixture resembles coarse crumbs.
3. Gradually add cold water until the dough forms a ball.
4. Wrap in plastic wrap and refrigerate for 30 minutes.
5. Roll out the dough and fit it into a pie dish.

Step 2: Pre-Bake the Crust

1. Preheat the oven to 350°F (175°C).
2. Prick the bottom of the crust with a fork to prevent bubbling.
3. Bake for 10-12 minutes, or until lightly golden.

Step 3: Make the Custard Filling

1. Beat the eggs in a large bowl until frothy.
2. Mix sugar, cornstarch, and salt in another bowl.
3. Warm the milk in a saucepan over medium heat, but do not boil.
4. Gradually whisk the warm milk into the eggs to temper them.
5. Return the mixture to the saucepan and cook over medium heat, stirring constantly, until thickened.
6. Remove from heat and stir in vanilla extract, shredded coconut, and butter.

Step 4: Assemble and Bake

1. Pour the custard mixture into the pre-baked crust.
2. Bake at 350°F (175°C) for 25-30 minutes, or until the filling is set and the top is golden.

Step 5: Cool and Chill

1. Allow the pie to cool at room temperature.
2. Refrigerate for at least 2 hours or overnight for best results.