Why does my pastry crack and crumble when I roll it?

Shortcrust is a balance between two things that fight: enough water to make the flour cohere, and little enough that gluten does not develop and make it tough. Recipes err towards dry because a tough pastry is a worse outcome than a crumbly one — which means the dough that arrives on your worktop is very often genuinely under-hydrated. The other half of the problem is temperature. Cold fat is solid, and a dough full of solid fat has no plasticity at all until it warms slightly.

What you'll need

• Cold water
• Cling film or a food bag
• A rolling pin

Step by step

1. Feel the temperature first.If it is hard and cold from the fridge, that alone will crack it. Leave it wrapped on the worktop for 15–20 minutes until it gives slightly under pressure but is still cool. Do not warm it in your hands.
2. If it is cool but crumbly, add water — carefully.A teaspoon of cold water at a time, worked in with your fingertips or a knife, until the dough just holds together when pressed. Under-hydrated pastry is far commoner than over-hydrated. Stop the moment it coheres.
3. Wrap and rest it.Half an hour in the fridge after any water is added. The flour needs time to absorb it evenly — a dough that feels wet in patches and dry in others will roll evenly after a rest even without more water.
4. Roll between two sheets of parchment or cling film.This is the single most useful technique for fragile pastry. It stops sticking without adding flour, supports the sheet, and lets you lift it into the tin without it collapsing.
5. Roll from the centre outwards, turning as you go.Quarter-turn between rolls, always pushing away from the middle. Rolling back and forth over the same line stretches the dough unevenly and opens cracks at the edges.
6. Patch rather than re-roll.Press cracks together with a fingertip, or take a scrap and press it over the hole with a dab of water. Re-rolling and re-kneading develops gluten and gives a tough pastry — patching costs nothing.
7. Check the fat and flour balance if it happens every time.A very high-fat pastry — pâte sablée, some sweet shortcrusts — is crumbly by design and is meant to be pressed into the tin rather than rolled. That is not a fault.

Tips

• Rest is nearly free and fixes more pastry problems than any other single action. Twenty minutes wrapped in the fridge changes a dough completely.
• Cold vodka or gin can replace part of the water in shortcrust: alcohol hydrates the dough without developing gluten, then evaporates. It is a real technique, not a gimmick.
• If the kitchen is hot, chill the flour and the bowl as well as the fat. Pastry in a 28°C kitchen is a different job.
• A food processor makes shortcrust in seconds but over-works it in a couple more. Pulse to breadcrumbs, add water, pulse until it just clumps, then finish by hand.

Common mistakes

• Flouring the worktop heavily to stop sticking — The extra flour goes into the pastry and dries it further, so the next roll cracks worse. Parchment solves it without changing the recipe.
• Balling up and re-kneading cracked pastry — Every re-knead develops gluten. The second attempt rolls better and bakes tougher and shrinks more.

If it doesn't work