Tart
A shallow open pastry case with its filling exposed, where nearly every fault is about the base cooking on a different schedule from everything above it.
Also called tart case (UK), tart shell (US), fruit tart (INTERNATIONAL), flan (UK) — In British usage a flan is close to an open tart; in Spanish and French usage the word names quite different things.
A tart is a shallow case of short pastry, open on top, holding a filling that may be baked with it or added afterwards. The construction is what generates its problems.
THE BASE IS THE HARDEST PART OF THE OVEN TO REACH. Heat arrives at the sides of a tart directly and at the base through a tin, a filling and often a layer of moisture. So the sides colour and crisp while the base is still pale and soft. Blind baking exists entirely to give the base a head start, and skipping it is the commonest reason for a soggy bottom.
SHORT PASTRY SHRINKS IF IT WAS STRETCHED. Rolled pastry that is pulled to fit the tin goes in under tension, and gluten under tension relaxes when heated — pulling the case back down the sides. Resting after rolling and easing rather than stretching the pastry into the tin are the fixes, and neither is about how the pastry was made.
THE FILLING DECIDES HOW MUCH PROTECTION THE BASE NEEDS. A wet fruit filling releases liquid into pastry that is trying to crisp; a set custard releases less but takes a long, gentle bake the pastry does not want. Sealing a blind-baked case with egg wash or a thin chocolate layer works because it puts a water-resistant barrier between the two.
BakeHQ treats a tart and a pie as different constructions rather than as regional names for one thing: a pie has a lid or a top crust and a tart does not, and the difference changes how steam leaves the filling.
What it should be like
- Structure
- Crisp short pastry that holds its shape when the tin is removed
- Crust
- Evenly coloured base and sides, not pale underneath
- Handling
- Rested before baking; eased into the tin rather than stretched
Blind baking, and what the beans are actually for
A pastry case baked empty does two things a filled one cannot: it dries and sets before any moisture arrives, and it browns on the base while the base is still exposed to heat.
The weight is there to stop it moving, not to conduct heat. Short pastry contains water that turns to steam, and steam under a sheet of pastry lifts it into a dome; the sides, unsupported, slump inward. Beans, rice or chain weights hold the shape until the structure has set enough to keep it.
Removing the weights for the last part of the bake is the step most often skipped, and it is where the base actually colours. A case that is pale underneath after blind baking has usually been baked entirely with its lining still in.
Related
Part of
Short paste, where texture comes from fat dispersed through flour.
Things that go wrong
The canonical tart fault, and the reason blind baking exists.
Pastry stretched to fit a tin pulls back, which is what this model is about.
Pastry cream is lumpy, runny or grainy
A filled sweet tart is usually filled with pastry cream.
What this product needs done
Structure building
Solid fat interrupting flour is what makes short pastry short.
Gluten inhibition
Worked pastry is tough pastry, and it shrinks.
Hydration
Enough water to bring it together and no more.
Characteristic ingredients
Plain flour; strength is not wanted.
Solid fat dispersed through the flour.
Enough to bring it together and no more.
In a sweet paste, for tenderness as well as taste.
Techniques involved
Fat dispersed through flour for shortness.
The answer to the base problem, and the reason it exists.
Eased in rather than stretched, or it will shrink.