Preheat the oven to 350°F (175°C).
In a large mixing bowl, combine the pumpkin puree, heavy cream, brown sugar, eggs, bourbon, vanilla, cinnamon, ginger, nutmeg, and salt. Whisk until smooth.
Pour the filling mixture into a prepared pie crust, smoothing the top with a spatula.
Bake in the preheated oven for 45 to 50 minutes, or until the filling is set but slightly jiggly in the center.
Remove the pie from the oven and allow it to cool completely on a wire rack, approximately 2 hours.
Once cool, sprinkle an even layer of granulated sugar over the top of the pie.
Using a kitchen torch, carefully caramelize the sugar until it turns golden brown and bubbly.
Let the brûléed layer cool for a few minutes before serving.