In a large bowl, combine all-purpose flour, cubed unsalted butter, granulated sugar, and salt. Use a pastry cutter or your fingers to mix until the mixture resembles coarse crumbs.

Add Ice Water

Gradually add ice water, one tablespoon at a time, mixing until the dough comes together. Form the dough into a disc, wrap in plastic wrap, and refrigerate for at least 30 minutes.

Roll and Fit the Dough

After chilling, roll out the dough on a floured surface to fit your pie pan. Carefully place the dough into the pan and trim the edges. Prick the bottom with a fork and set aside.

Filling

Preheat the Oven

Preheat your oven to 350°F (175°C).

Mix the Filling

In a mixing bowl, combine chopped walnuts, semi-sweet chocolate chips, granulated sugar, brown sugar, corn syrup, eggs, bourbon, vanilla extract, and salt. Stir until well combined.

Fill the Crust

Pour the filling mixture into the prepared pie crust, spreading it evenly.

Bake the Pie

Bake in the preheated oven for 45-50 minutes, or until the filling is set and the top is slightly puffed. Let it cool on a wire rack.

Chocolate Drizzle

Prepare the Drizzle

In a small saucepan over low heat, combine semi-sweet chocolate chips and heavy cream. Stir until the chocolate is melted and smooth. Remove from heat and let cool slightly.

Whipped Cream Topping

Make the Whipped Cream

In a mixing bowl, beat heavy cream, powdered sugar, and vanilla extract until soft peaks form.

Serve the Pie

Slice the cooled pie, top each slice with a generous dollop of whipped cream, and drizzle with chocolate sauce before serving.