Pies and tarts are like fraternal, rather than identical, twins. There is a family resemblance, but they have important differences. Both pastries include flour, a liquid, and a fat. Unlike a pie crust, however, traditional tart pastry always is made with butter rather than shortening, and in a greater proportion, so much so that another name for tart pastry is "short" dough, meaning high in fat (like shortbread cookies). The extra fat coats the flour particles in the dough so that they absorb less liquid. As a result, the strands of structure-building proteins that develop when flour mixes with water are literally shorter than they would be otherwise. The crust bakes rich and crumbly, rather than flaky.
In addition to more fat, tart dough also incorporates egg yolks for strength and color, and often sugar for sweetness. On the other hand, this rich pastry may be overwhelming for some fillings, so a tart recipe may call for regular pie pastry, or even a cookie crust, for balance. Follow our Tart Pastry recipe when a traditional tart crust is called for.
Measuring the Dough
Roll out dough on a floured surface to a circle 2 inches larger than the diameter of the tart pan. To make sure that the dough circle is the correct size, lay the pan on the dough and measure the margin with a ruler.
Fitting the Dough in the Pan
Transfer the dough from the work surface to the pan as for a one-crust pie. With one hand, lift up a section of the overhanging dough and ease into the pan. Use a small ball of dough, your fingers, or the heel of your hand to push against the inside of the dough so it fits snugly, especially where bottom and sides meet.
Trimming with a Rolling Pin
To remove excess dough, roll around the entire edge of the pan with a rolling pin. Use an even, smooth action. The overhanging dough will drop off, leaving a neat edge.
Trimming with your Fingers
Instead of using a rolling pin, you can use your thumb to trim away the extra dough. Lift up the dough with one hand, and push across the rim of the tart pan with the thumb of your other hand.