It is indeed best to choose a cool dry day on which to make layered dough; heat and humidity both cause problems. The tools and equipment required for making layered doughs are the same as those needed for pie crusts; a cool marble work surface is ideal but not essential. Keep in mind that these are the most challenging and delicate of pastries, and proceed the way porcupines, according to the old joke, are said to make love: very, very carefully.
To make any kind of layered dough, a large block of butter, wrapped in the dough like a package, must be rolled out and folded, rerolled and refolded. The idea is to create thin, even layers of butter between distinct layers of dough rather than integrating dough and butter. For this to work, the butter and the dough must be similar in temperature and consistency so that they move together at an even pace under the pressure of the rolling pin. If the butter is too cold and hard, the pressure of the rolling pin may push it through the dough layer instead of extending it, resulting in nonuniform layers. Fortunately, it is possible to see and feel the butter cracking in the dough as it is rolled out, enabling the cook to stop and let the dough rest and the butter soften a bit. Butter that is too soft is even worse though: The dough and butter merge under pressure from the rolling pin instead of maintaining their separate identities. If the dough seems to squishy and/or the butter oozes from it as you roll, stop and refrigerate them until firm but still pliable. And at no point allow the dough to absorb excess moisture or dry out.
To roll the dough, flour the work surface and the dough or the rolling pin lightly. (Use only as much flour as needed to prevent sticking, for excess flour will toughen the pastry and turn it gray.) Always position the dough with the short end in front of you. Roll the dough with even pressure to maintain an even thickness. Keeping the pin parallel to the work surface, roll from the center of the dough away from you and then from the center of the dough back toward you, lifting the pin after each roll. Rolling back and forth without lifting the pin develops the gluten in the dough, making it tough and elastic. Never roll the pin over the edge of the dough. Roll the dough the long way to the desired length and then adjust the width if necessary. As you roll the pastry to the desired size, maintain the doughΓÇÖs rectangular shape, keeping the corners square, the sides of the dough as straight as possible, and the thickness even. Straighten the sides of the dough occasionally with your hands, as though straightening a stack of papers, or press the sides with a pastry scraper or rolling pin. If the dough becomes misshapen, correct it with the rolling pin, rolling specifically on the side that is uneven before proceeding. If a small area of butter becomes uncovered when the dough is being rolled, gently pat a little flour over the butter spot and brush off any excess flour. Brush excess flour from the dough with a dry pastry brush before folding.
The folding technique and the number of turns required vary according to the type of pastry. Classic puff pastry is given 3 sets of 2 turns each, for a total of 6 turns, and the folding is always in thirds, like a business letter; this is called a single fold. Food processor (the recipe we give here) and quick puff pasry are given 4 turns, but 3 of these are double folds. In a double fold, the top and bottom of a long rectangle are folded to the center; the rectangle is then folded in half. Croissant dough is given 4 turns with single folds, and Danish pastry dough, 5 turns with single folds.
To avoid excess gluten development, the dough should be rotated after every single turn so that the gluten strands are stretched in a different direction with each successive turn. The dough is wrapped in plastic wrap, refrigerated, and allowed to rest for 30 to 60 minutes (depending on the pastry) between the turns. The rest relaxes the gluten strands and lets them adjust to their new length; chilling firms the butter, which helps keep the layers of dough and butter distinct. (Do not allow the butter to turn hard or brittle while chilling; if this occurs, remove the dough from the refrigerator and let it sit on the counter for 10 minutes or so until the butter reaches a pliable state.) The dough is chilled again after the finished dough has been rolled into a sheet and before it is cut into shapesand often still again just before baking. (Read each recipe for specific instructions.) It is surprisingly easy to lose track of how many turns you have given the dough as it rests. Professional bakers make a shallow fingertip imprint in the dough, one for each turn, before they refrigerate the dough for its resting period.
