Prepare the crust. Combine the crushed graham crackers, melted butter, sugar, and salt in a bowl. Stir until the crumbs are evenly moistened and resemble damp sand.
Press into the pie dish. Transfer the mixture to a 9-inch pie dish. Firmly press the crumbs across the bottom and slightly up the sides. Refrigerate while preparing the filling.
Make the pudding mixture. Whisk the instant butterscotch pudding mix and cold milk in a large bowl until smooth and thickened.
Add the bourbon. Whisk in the bourbon, vanilla extract, and salt until evenly incorporated.
Whip the cream. In a separate bowl, beat 1 cup of heavy whipping cream with 1/4 cup powdered sugar until soft peaks form.
Fold the cream into the filling. Gently fold the whipped cream into the butterscotch pudding mixture using a rubber spatula. Avoid vigorous stirring so the filling stays light and fluffy.
Make the topping. Beat the remaining 1 cup heavy whipping cream with 2 tablespoons powdered sugar and vanilla until medium to stiff peaks form
Top the pie. Spread or pipe the whipped cream over the filling. Sprinkle with chopped pecans and add a light drizzle of butterscotch sauce if desired.
Chill. Cover the pie and refrigerate for at least 4 hours, or preferably overnight, until firm.
Serve. Slice the chilled pie with a sharp knife. For cleaner slices, warm the knife under hot water, wipe it dry, and cut the pie.
