In a food processor, pulse together flour, granulated sugar, and salt until well combined. Add cold, cubed unsalted butter and pulse until the mixture resembles coarse crumbs. In a small bowl, whisk together the egg, vinegar, and a few tablespoons of cold water. Gradually add this mixture to the flour blend, pulsing until the dough begins to clump. Chill the dough in the refrigerator for 30 minutes.

Preheat your oven to 375°F (190°C). On a floured surface, roll the chilled dough into a 12-inch circle. Carefully transfer the rolled dough to a 9-inch pie plate, pressing it into the bottom and up the sides. Trim any excess dough and crimp the edges, then prebake the crust for 15 minutes. Brush the surface with egg white, then lower the oven temperature to 350°F (175°C).

In a large mixing bowl, whisk together eggs, pure canned pumpkin, sour cream, bourbon, and vanilla extract until smooth and well-combined. In a small saucepan, heat the pure maple syrup over low heat until it begins to simmer. Remove from heat and stir in heavy cream until fully integrated. Carefully blend this mixture into the pumpkin filling, ensuring a creamy consistency.

Pour the luscious filling into the pre-baked crust, smoothing the top with a spatula. Bake the Bourbon Brûlée Pumpkin Pie in the oven for 55-60 minutes, or until the filling is set with just a slight jiggle in the center. Once done, remove it from the oven and let the pie cool completely on a wire rack, preferably overnight for the best flavor.

Just before serving your Bourbon Brûlée Pumpkin Pie, sprinkle an even layer of granulated sugar over the top. Using a kitchen torch, carefully caramelize the sugar until it forms a golden-brown crust. Alternatively, you can place the pie under a broiler for 1-2 minutes—watching closely to avoid burning. Let the topping cool for a minute before slicing and serving.