01 - Set oven temperature to 400°F (200°C) before beginning preparation.
02 - Fit the unbaked 9-inch pie crust into a pie pan, trimming and crimping edges as needed.
03 - Pour 1 1/2 cups water directly into the pie crust.
04 - In a mixing bowl, blend 3/4 cup granulated sugar with 3 tablespoons all-purpose flour until uniform. Evenly sprinkle over the water in the crust.
05 - Drizzle 1 teaspoon vanilla extract across the surface and add a pinch of salt.
06 - Slice 4 tablespoons unsalted butter into thin pats and distribute evenly on top.
07 - Carefully position the pie on the lower oven rack and bake for 30 minutes at 400°F (200°C).
08 - Lower oven temperature to 375°F (190°C) and bake for 20 additional minutes until the crust is golden brown and filling sets with a slight jiggle.
09 - Remove from oven, cool completely to room temperature, then refrigerate pie at least 2 hours before slicing for optimal texture.