1cupunsalted butter – chilledcut into tablespoon-size pieces
Make the pie crust
Combine flour, salt, and butter in a food processor. Pulse until mixture resembles coarse crumbs, about 10 1-second pulses.
Stir water and vinegar in a small bowl.
Pour half the ice water and vinegar mixture into the flour and butter mixture. Pulse to combine, about 3 (1-second) pulses. Pour in remaining ice water and vinegar mixture. Pulse until mixture just starts to come together, about 8 (1-second) pulses.
Turn dough out onto a wooden surface, pat into round shape and divide in half. Form each half into a disc about 15cm wide.
Wrap each disc in plastic wrap and refrigerate for at least 30 minutes until ready to use.
To make the pie
Preheat oven 220 degrees C
Whisk together pumpkin puree, egg yolks, and egg in a large bowl until smooth. Add sweetened condensed milk, cinnamon, ginger, salt, nutmeg, and Chinese 5-spice powder; whisk until thoroughly combined.
Fit pie crust in a 20cm pie dish and crimp edges.
Pour filling into the pie shell and lightly tap on the work surface to release any air bubbles.
Bake in the preheated oven for 15 minutes.
Reduce heat to 175 degrees C and bake until just set in the middle, 30 to 40 more minutes. A paring knife inserted into the filling, 10cm from the crust, should come out clean. Allow to cool completely before serving.