Pie: Everything You Need to Know About Sweet and Savoury Pies

A pie is a savoury dish or sweet bake made of a filling and pastry. The pastry, called pie dough, can sit underneath, on top, or even wrap the whole filling. Pie dough used to be made from simple ingredients: flour, salt, water and fat, originally animal fat (lard). Few people use lard today, not only because it is hard to find but probably also for health reasons, so butter and shortening are used instead, or blended in with the fat, because lard has the advantage of making pastry crisp and crumbly.

Pie is well known in Western cuisine, especially sweet pie. Its defining feature is the pastry that holds or wraps the filling, adding dimension and texture to the dish. There are many kinds of pie dough, such as savoury and sweet. Pie is an important part of French cuisine: fine-dining restaurants serve dishes made with pastry, such as pâté en terrine (in French, pâté means pie), or use pastry as a decorative touch on the plate. In American cuisine, pie is more of an everyday comfort food or a home cook's staple, such as apple pie, cherry pie and pecan pie.

Types of Pie

1. Baked pie: a pie meant to be eaten warm.
2. Open-top pie: for example quiche and pumpkin pie. The pastry base is usually half-baked first, then filled, to keep it crisp. This method is called blind baking.
3. Double-crust pie (two-layer pie crust): the pastry and filling are baked together. The filling is drier than in an open pie, such as apple pie, or is pre-cooked, as in chicken pie or coconut pie. The top crust must be pierced to let steam escape so the filling stays dry and the pastry doesn't turn soggy.
4. Unbaked (chilled) pie: as the name suggests, eaten cold. The base and filling are prepared separately and assembled later, for example fruit pie, lemon meringue pie, or pies with mousse or custard fillings. Later chilled pies often use crushed biscuits or cookies instead of pastry to save effort, as in blueberry pie and banoffee pie.

The Components of Pie Dough

Since there are many types of pie dough, let's start with standard pie dough rather than puff pastry. It has four components:

1. Wheat flour: the gluten level matters. All-purpose flour is best for pie, with medium protein (gluten) that gives a pleasantly crumbly dough that isn't too dense or hard. (If you use high-protein bread flour, the pastry will be tough and you'll need more fat to soften it.)
2. Fat: makes pastry crisp, fragrant and rich. You can use butter, shortening or even lard. The less water a fat contains, the crisper and more crumbly the pastry, as with lard. However, lard isn't popular in European pies, which favour butter for flavour and aroma. Some bakeries blend butter and shortening to cut costs and make the dough easier to roll.
3. Salt and sugar: affect the flavour, colour and texture of the pastry. Sweet pastry with plenty of sugar bakes darker than savoury pastry, and it isn't as crumbly, because sugar contains water.
4. Liquids such as water, egg and milk bind the dough together. Too much liquid makes the pastry dense and hard, because water activates gluten during mixing; too little and the dough won't come together. Water and milk behave differently: pastry made with water is crisper than pastry made with milk. Eggs (or just yolks in some recipes) add colour and richer flavour, mostly in sweet pastry.

Common Problems When Making Pie

For experienced bakers, pie is rarely a problem, but first-timers may run into issues such as soggy, soft pastry or dough that won't roll. Here are some techniques in brief.

Crisp pastry depends on temperature and technique. Most pie doughs begin by rubbing the dry ingredients (flour, salt, sugar) with cold butter until the mixture resembles coarse crumbs. This disperses the butter throughout, coated in flour. The key is that the butter must be cold so it coats the flour in small pieces (except for sweet pastry, pâte sucrée, where the butter and sugar are creamed first). The liquid added next must also be cold. Cold temperatures reduce gluten formation and stop the butter from melting.

Mixing Pie Dough

Mix only until the dough is smooth and comes together. Kneading too long develops gluten and makes the pastry hard. After mixing, rest the dough in the fridge so it relaxes and won't shrink when rolled or baked, and so the butter firms up again and the dough doesn't turn soft and sticky when rolled.

How to Roll Pie Dough

Take the rested dough out of the fridge; it should give slightly when pressed with a finger. Lightly dust the table, baking paper or a silicone mat with flour, place the dough on it and cover with cling film. Roll the dough to about 0.3 cm thick. Lift the baking paper with the dough, flip it so the cling film side is on the table, and peel off the baking paper. Then lift the cling film with the rolled dough, gently lay it in the tin, peel off the film and trim the dough to fit.

Baking Pie

Bake at around 180–200°C; any lower and the pastry will be soggy. Properly baked pastry is golden and, once cooled, crisp and crumbly when broken. Place the baked pie on a rack to cool completely before removing it from the tin.