Perfect shortcrust pastry depends on simple details: cold butter, minimal handling, and enough resting time.
When the dough stays cool, it bakes crisp and tender instead of tough.
This basic method works for sweet or savory tarts.
Place the flour, salt, and optional sugar in a bowl. Add the cold butter cubes and rub them into the flour until the mixture looks sandy with a few small butter pieces left.
Add the egg yolk, then cold water one tablespoon at a time. Mix just until the dough comes together. Do not knead, because too much handling can make the pastry tough.
Shape the dough into a flat disc, wrap it, and chill for at least 30 minutes. Roll it on a lightly floured surface, then place it in the tart pan.
For blind baking, prick the base, cover with baking paper and weights, then bake at 180°C for 15 minutes. Remove the weights and bake 8 to 10 minutes more.
For perfect shortcrust pastry, keep the butter cold, add water gradually, avoid kneading, and chill the dough before rolling.