The different types of tart shells include standard size, miniature, frozen, fresh, pre-baked, flaky and puff pastry. There are also crumb crust shells and those with lattice shell tops as well as single or double versions. Sometimes, a metal pastry ring of dough is placed on top of a baking sheet lined with parchment paper to create a tart. Typically though, most types of tart shells, which are usually round but sometimes rectangular, are made with shallow, fluted edge pans that have removable bottoms.
What is commonly considered as the standard size of tart shell is 9-10 inches (23-25.4 cm) in diameter. Small shells vary from about 2-4 inches (5-10 cm) in diameter. Both sizes of shell may be filled with savory or sweet foods. Fruit and cheese fillings are usually baked in an uncooked shell, while custards and creams are added to cooled, pre-baked tart shells.
Puff and flaky are the two kinds of pastry commonly used to make shells for tarts. Flaky pastry is typically sweet, while puff pastry often has no sugar added to it. For this reason, puff pastry tart shells are often used for savory ingredients such as herbs, meat or cheese, while a flaky shell recipe tends to be more appropriate for dessert fillings.
Puff pastry involves repeated rolling out and folding of the dough and this creates much crisper layers that the softer, flakier tart shells. A greater proportion of butter or shortening added to flaky tart shell dough can result in soft flakes in the baked crust. Some bakers prefer butter while others like to use only shortening or half of each kind of fat to get the flakiest possible tart shell.
A single shell for tarts lines the pan and holds the filling, but leaves it open on top. Pre-baked single shells are ideal for custard or cream tarts. Single crust tart shells may be frozen unbaked, then baked without thawing them first. Double crusted tarts may be baked with a meat or fruit filling. Lattice tart shells, like some pie crusts, have a top that partially shows the filling as it consists of woven strips of dough spaced evenly apart.
Crumb crust tart shells may be made with crushed cookies mixed with melted butter. This mixture is pressed into the bottom and sides of a tart pan, then baked. Alternatively, a blend of flour, sugar, beaten eggs and melted butter may be used to make the crumb shells. Ground nuts, oats, cocoa, coconut and spices such as cinnamon may be added to the basic crumb shell mixture. After baking and cooling, a sweet filling such as chocolate-pecan may be added to the crumb tart shell; crushed cookie or other dessert crumbs may be sprinkled on top.