01 - Preheat the oven to 400°F (200°C).
02 - Fit the unbaked pie crust into a 9-inch pie pan, crimping the edges for a decorative finish.
03 - Pour the measured water directly into the pie crust.
04 - Combine granulated sugar and all-purpose flour in a mixing bowl until evenly blended. Sprinkle the mixture uniformly over the water.
05 - Drizzle vanilla extract over the surface, add a pinch of salt, and arrange sliced butter evenly across the top.
06 - Transfer the pie pan to the lower rack of the oven. Bake for 30 minutes at 400°F (200°C).
07 - Reduce oven temperature to 375°F (190°C) and continue baking for 20 minutes, or until the crust is golden and the filling shows a gentle wiggle in the center.
08 - Remove from the oven and cool completely to room temperature. Refrigerate for a minimum of 2 hours before slicing to achieve optimal texture.