For pie crust:
- In a bowl (or in a food processor), combine flour and salt. Add butter and use a pastry blender (or pulse in the processor) to cut the butter until pieces are the size of lentils. Drizzle in the water and stir (or pulse) until the crumbs are moistened and the dough holds together when pressed; turn out onto a piece of plastic wrap. Gather into a ball, flatten, wrap in plastic and refrigerate for 30 minutes. Roll into an 11-inch round with a rolling pin.
- Preheat the oven to 350°. Line a 9-inch pie plate with all butter pie crust, pressing down gently. Refrigerate about 15 minutes to allow the crust to relax (so it will shrink less on baking).
- Line the pastry with foil or parchment and fill with pie weights or dried beans. Bake for 30 minutes, or until nearly cooked through and dry to the touch. Carefully remove the foil and weights. Bake for 10 minutes longer, until golden. Let cool completely. (Beans may still be used in soup etc after serving as pie weights.)
- In a medium saucepan, combine the sugar, flour and salt and stir to mix evenly. Using a whisk (preferable) or a spoon, stir as you add whole milk. Set over moderate heat and, whisking very often, cook until the mixture just begins to boil.
- Put the eggs in a bowl and briskly whisk in 1/2 cup of the hot milk mixture. Whisk the egg mixture in the bowl back into the saucepan and cook over moderate heat, whisking constantly until thickened, about 2 minutes. Stir in all but ¼ cup coconut and the vanilla.
- Spoon the custard into the baked pie crust and refrigerate for at least 2 hours.
- In a 350° oven, toast the remaining coconut for 5 to 10 minutes, stirring often, until it is light brown.
- Put the cream in a bowl and use an electric mixer to beat until stiff. Spread on chilled pie and sprinkle with toasted coconut.