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.
2. In a medium saucepan, combine milk and 1 cup of heavy cream. Heat over medium heat until steaming but not boiling.
3. In a separate bowl, whisk together sugar, cornstarch, salt, and egg yolks until smooth.
4. Slowly pour the hot milk mixture into the egg mixture, whisking constantly to prevent curdling.
5. Return the mixture to the saucepan and cook over medium heat, stirring constantly, until thickened (about 5-7 minutes).
6. Remove from heat and stir in butter, vanilla extract, and toasted coconut. Pour the filling into the baked pie crust.
7. Cover with plastic wrap, pressing it directly onto the surface of the filling to prevent a skin from forming. Chill for at least 4 hours or overnight.
8. Before serving, whip the remaining 1/2 cup of heavy cream until stiff peaks form. Spread over the pie and garnish with toasted coconut.