Chill all ingredients 30 minutes prior to making crust.
In a large mixing bowl, sift together flour and salt. Using a pastry blender, cut butter into flour until mixture resembles coarse sand. Stir in water, a tablespoon at a time, until comes together. Form dough into a ball and wrap in plastic. Chill thoroughly, up to overnight, before rolling out.
Pre-heat oven to 350 F.
On a lightly floured surface with a rolling pin, roll dough out to fit a 9-inch pie plate. Place crust in pie plate. Press the dough evenly into the bottom and sides of the pie plate. Flute the edges, if desired.
Line the crust with aluminum foil and add pie weights or dry beans. Bake in preheated oven for 10 to 15 minutes until golden brown. Remove from oven, and remove foil and pie weights. Cool in the pie pan on a wire rack until room temperature, before filling.
Preheat oven to 350 F. Spread shredded coconut on ungreased baking sheet and toast, stirring occasionally, until light-golden brown, about 5 minutes. Be careful to watch the coconut closely. The sugar will quickly burn if left unattended.
In a medium saucepan, combine the half-and-half, eggs, sugar, flour and salt and stir well to combine. Bring to a boil over low heat, stirring constantly. Remove the pan from the heat, and stir in 3/4 cup of the toasted coconut and the vanilla extract. Reserve the remaining coconut to top the pie. Pour the filling into the pie shell and chill until firm, about 4 hours.
Top with whipped topping and remaining coconut.