1. Prepare the Crust:

1. Preheat oven to 350°F (175°C). Spread shredded coconut on a baking sheet and toast for 5-7 minutes until lightly golden. Set aside to cool.
2. In a medium saucepan, whisk together sugar, cornstarch, and salt. Gradually whisk in milk until smooth.
3. Cook over medium heat, stirring constantly, until mixture thickens and comes to a boil. Boil for 1 minute, then remove from heat.
4. In a small bowl, beat egg yolks. Gradually whisk in 1/2 cup of the hot milk mixture to temper the yolks. Pour the yolk mixture back into the saucepan and return to heat.
5. Cook for 2 more minutes, stirring constantly. Remove from heat and stir in butter, vanilla, and 3/4 cup of the toasted coconut.
6. Pour the filling into the pre-baked pie crust. Cover with plastic wrap, pressing directly onto the surface to prevent a skin from forming. Chill for at least 4 hours.
7. Before serving, whip the heavy cream with powdered sugar until stiff peaks form. Spread over the chilled pie and sprinkle with remaining toasted coconut.