Mix flour, sugar, and salt in a food processor or blender. Add butter and pulse until a coarse meal forms. Be sure not to pulse too long, the butter should be no smaller than the size of peas. Slowly add in just enough ice water to form moist clumps. Gather the dough into a ball and divide in half (you can use a kitchen scale if you want them to be perfectly even). Form dough into 2 balls and gently flatten into disks. Wrap each disk in plastic and place in the refrigerator to chill for at least one hour. You will only need one disk of dough for this recipe, so you may want to place the other disk in the freezer until needed.

In a heavy-bottomed skillet or saucepan, melt the butter over medium-low heat. Continue cooking the butter after it's melted, whisking frequently, until the butter begins to foam and turns a deep golden brown. Whisk in the light brown sugar and remove from heat. Pour the butter/sugar mixture into a large bowl. Add in the pumpkin puree and sweetened condensed milk and whisk smooth. Whisk in the egg, yolks, vanilla, and spices and beat until well combined, about 1 minute.

Preheat oven to 400 degrees (F). Lightly grease a 9" pie plate with non-stick spray OR butter and a little flour; set aside.

Roll out half of the chilled dough on a lightly floured work surface, rolling it to about a 12-inch round. Gently place the dough into the prepared pie dish and trim the edges OR crimp them decoratively.

Sprinkle the bottom of the pie shell with 1 teaspoon of flour (this helps soak up excess moisture) then add the pumpkin pie filling. Bake in preheated oven for 20 minutes, then reduce the heat to 350 degrees and bake for an additional 40 minutes, or until the edges are set but the center is still just a a little wobbly.

Cool on a wire rack for one hour, then place the pie in the fridge for at least another 2 hours before slicing. Serve with whipped cream or ice cream.