To make the pie crust, whisk together flour, sugar, and salt in a large bowl. Add butter and mix with a pastry blender or fork until the mixture resembles coarse meal and the butter is the size of small peas.
Add 1 tablespoon of water and continue mixing. Add more water as needed, 1 tablespoon at a time, until a dough forms. Wrap the dough tightly in plastic wrap. Refrigerate for at least 2 hours.
Remove dough from refrigerator. If necessary, let it sit at room temperature for 10 to 15 minutes until slightly softened but still cold.
Lightly flour work surface. Roll out dough into a circle about 1/8-inch thick.Transfer the dough to a lightly greased 9-inch pie plate. Trim any excess dough from the edges.
For a simple fluted edge, press the knuckle of one finger into the rim of the crust while holding two fingers about a half inch apart on either side of your knuckle. Repeat around the entire edge of the crust.
Preheat oven to 350°F. Line the crust with parchment paper so that the paper overhangs on all sides. Fill pan with pie weights (or dried beans).Bake for 20 to 25 minutes, or until edges are browned.Remove weights and lining. Cool completely.
To make the filling, first place nuts in the baked pie crust. Set aside.
Place sugar and water in a medium heavy saucepan. Cook over medium heat, stirring constantly, until sugar is dissolved.
Increase heat to medium-high and continue cooking, without stirring, until mixture turns amber. Be sure to watch closely to prevent burning.
Remove from heat and carefully add cream. (Mixture will bubble.) Stir until combined. Add butter, corn syrup, vanilla, and salt. Stir until combined and smooth.
Pour caramel over nuts in pie crust. Sprinkle with coarse salt. Allow to sit at room temperature for 15 minutes. Then, refrigerate until set.