Mix the flour and salt in a bowl. Add the cold butter and rub it into the flour with your fingertips until the mixture resembles coarse crumbs with a few small butter pieces. If the butter becomes greasy, chill the bowl before continuing.

Drizzle in 3 tablespoons of the cold water and mix with a fork. Add the remaining tablespoon in small amounts only if needed. Stop when a handful holds together when pressed; the dough should not be wet or sticky.

Gather the dough with gentle pressure and flatten into a disk about 1 inch thick. Wrap and refrigerate for 30 minutes. Do not knead it smooth like bread.

Let the chilled dough stand briefly only if too firm to roll. Roll on a lightly floured surface to a circle about 12 inches across and 1/8 inch thick. Ease into a 9-inch tart tin without stretching, press gently into the corners and trim the edge. Patch small cracks with dough scraps. Chill the lined tin for 20 minutes.

Heat the oven to 375°F (190°C). Set the tin on a baking sheet. Line the pastry with baking parchment and fill with pie weights, supporting the sides as well as the base.

Bake for 20–25 minutes until the rim looks dry and begins to color. Carefully lift out the parchment and weights. Prick any raised patches on the base gently with a fork.

For a fully baked shell, return to the oven for 10–15 minutes until the base is dry and golden. For a filling that needs further baking, return for about 5 minutes just to dry the base, then follow that filling recipe for the final bake. Let a fully baked shell cool in the tin before filling or removing the outer ring.