Prepare the Crust: In a food processor, pulse together the flour, granulated sugar, and salt until combined. Add cubed unsalted butter and pulse until a coarse crumb forms. In a bowl, whisk together the egg, vinegar, and cold water, then drizzle this mixture into the processor while pulsing until just combined. Chill the dough for 30 minutes, then roll it out to a 12-inch circle and fit it into a 9-inch pie plate. Pre-bake the crust at 375°F for 15 minutes, brush with egg white, and reduce the oven temperature to 350°F.

Make the Filling: Whisk together the eggs, pure canned pumpkin, sour cream, bourbon, vanilla extract, and spices in a large mixing bowl until smooth. In a small saucepan, heat the maple syrup until it simmers, and then remove it from heat. Carefully whisk in the heavy cream until combined, then pour this mixture into the pumpkin filling and stir until fully incorporated.

Bake the Pie: Pour the smooth filling into the pre-baked crust, spreading it evenly. Bake in the 350°F oven for 55-60 minutes or until the center of the pie jiggles slightly when shaken. Remove the pie from the oven and allow it to cool to room temperature before refrigerating.

Brûlée Topping: When ready to serve, evenly sprinkle granulated sugar across the top of the pie filling. Using a kitchen torch, caramelize the sugar until it forms a crispy, golden layer. If you don’t have a torch, place the pie under a broiler set to low for a few minutes, watching closely to prevent burning.