To make the pastry: combine the flour, ground pecans, sugar, and salt in a large mixing bowl. Add the butter and mix with a pastry blender or your hands until the mixture resembles coarse crumbs. Pour in the ice water and work it in to bind the dough until it holds together without being too wet or sticky. Squeeze a small amount together, if it is crumbly, add more ice water, 1 tablespoon at a time. Wrap the dough in plastic wrap and refrigerate for at least 30 minutes.
Roll out the dough on a lightly floured surface into a 12-inch circle. Carefully roll the dough up onto the pin (this may take a little practice) and lay it inside a 9-inch pie pan. Press the dough into the pan so it fits tightly and trim the excess around the rim. Place the pie pan on a sturdy cookie sheet so it will be easy to move in and out of the oven.
Preheat the oven to 350 degrees F.
To make the filling: melt the butter and chocolate in a small saucepan over medium-low heat, remove from heat and let cool. Beat the eggs in a large mixing bowl until frothy and then blend in the sugar. Stir in the syrup, vanilla, bourbon, salt, and the melted butter mixture until well blended.
Arrange the pecans on the bottom of the pie crust and carefully pour the egg mixture over them. Bake until the filling is set and slightly puffed, about 45 minutes. Test for doneness by sticking a thin knife in the center of the pie, if it comes out pretty clean, you're good to go. Transfer the pie to rack and cool completely before cutting.