In the bowl of a food processor, pulse together the flour and the Stirling Creamery butter until the mixture resembles a fine crumble. Add the water, bit by bit, until a dough forms. Pat the dough into a disk and wrap in plastic wrap. Refrigerate for at least 45 minutes.
Preheat the oven to 375 °F (190 °C). Roll the dough to ⅛" thick (~14" diameter circle) and transfer to a pie tin (preferably dark metal). Trim and crimp the edges. Chill while you prepare the filling
In a medium bowl, whisk together the syrup, sugar, and eggs, then whisk in the milk.
Pour the filling into the chilled tart shell and bake on the bottom oven rack for approximately 50 minutes (note the filling will still seem very fluid and jiggly, but you will notice some spots where it's beginning to bubble and brown).
Let the pie chill on a wire rack for at least 4 hours, then overnight in the fridge.