11 ounces (308 g) canned pumpkin puree or roasted sweet potato puree*
3 eggs (150 g, weighed out of shell), at room temperature
10 fluid ounces evaporated milk or heavy whipping cream (or half of each), at room temperature
3 tablespoons (42 g) unsalted butter, melted and cooled briefly
3/4 cup (164 g) packed light brown sugar
1/4 cup (50 g) granulated sugar
1/2 teaspoon kosher salt
2 teaspoons pumpkin pie spice**
2 tablespoons (18 g) all purpose gluten free flour (any of my preferred blends will do, with or without xanthan gum)
*To make the sweet potato puree, wash and pierce 3 medium (or 5 small) sweet potatoes with a fork. Place them on a baking sheet and bake, at 375°F, until the skin loosens and the flesh is very soft (anywhere from 30 minutes to an hour or more, depending upon the size of the potatoes). Allow the sweet potatoes to cool until they can be handled, and peel the skin from the flesh. Place the roasted sweet potato flesh in a food processor fitted with the steel blade, and process until smooth.
**To make your own pumpkin pie spice, combine 1 teaspoon ground cinnamon + 1/2 teaspoon ground ginger + 1/4 teaspoon ground allspice, 1/4 teaspoon ground cloves + 1/8 teaspoon ground nutmeg.
Prepare the pie crust according to the recipe instructions, through and including the parbaking of the pie crust. Keep the oven temperature at 375°F.
While the crust is parbaking, prepare the filling. In a large bowl, place the pumpkin or sweet potato puree, eggs, milk or cream, and melted butter, and whisk vigorously to beat the eggs and combine the mixture very well. It should be smooth, and will be quite thin if you used evaporated milk, thicker if you used heavy whipping cream. Add the brown sugar, granulated sugar, salt, pumpkin pie spice and flour, whisking until just combined after each addition. If you used evaporated milk, the mixture will be thin. If you used heavy whipping cream, the mixture will be thicker and creamier.
Once the crust is done parbaking, remove it from the oven and allow it to sit for a couple of minutes before removing the parchment paper and pie weights. Pour the prepared filling into warm crust, and smooth into an even layer. Return the crust to the oven and bake for 15 minutes. Reduce the heat of the oven to 350°F and bake until the edges are puffed and set, and the center jiggles only slightly and in a controlled, rather than a loose, way when the pie is shaken from side to side (about another 25 minutes). Remove from the oven and place the pie plate on a cooling rack.
Allow the pie to cool for at least 45 minutes or until cool to the touch before covering tightly with plastic wrap and placing in the refrigerator to chill until firm (about 1 1/2 hours). Remove the pie from the oven and allow to sit at room temperature for 30 minutes before slicing and serving.