Trimming and Baking
After transferring the dough to the pie plate, the overhanging edge must be cut off. When the excess dough is trimmed and turned under, it forms a thick rim that is both decorative and practical. Not only does it frame the pie, it also holds in the filling and adds support should the sides shrink during baking. Like soft clay, pie dough is very responsive. Crimp it, flute it, pinch it into points; the result is edible art.
Some crusts are either partially or fully baked before filling so they will stay crisp. Crusts for custard or cream pies, for example, are partially baked; crusts for uncooked fresh fruit, a chilled mixture such as mousse, or a cooked pastry cream or citrus curd are fully baked. To make a partially baked shell, weight the crust with heavy-duty aluminum foil to keep it flat during baking. To make a fully baked pastry shell, first prick the crust evenly with a fork so it won’t puff up and lose its shape. To prevent the edge of an unbaked filled pie from overbrowning, cover it during the early stages of baking with a foil shield that you can easily make yourself.
Trimming the Bottom Crust
With sharp kitchen scissors or a knife, trim the dough to 1/2-inch beyond the edge of the pie plate. Fold the excess under to build up a thick rim for crimping.
Partially Baking a Crust
If the dough is to be partially baked before it is filled, line it with a double thickness of heavy-duty foil to keep it from puffing up in the oven. Form the foil before you place it in the pie plate, or mold it around another pie plate of the same size.
Fully Baking a Crust
When a crust needs to be fully baked before filling, it must first be pricked all over so that the steam built up during cooking can escape. Then line the crust with a double thickness of foil, as shown in step 2.
Placing a Foil Shield
Covering the edge of an unbaked, filled pastry shell with aluminum foil during the initial stage of baking will prevent it from overbrowning. To make a shield, fold a 12-inch square of heavy-duty foil in quarters, then cut or tear a quarter circle 3 1/2 inches from the point to make a 7-inch hole. Unfold and place over the pie.