Learning to work with pastry can be one of the most difficult things in the dessert field, but once you have mastered the basics, your repertoire will increase exponentially. One of the trickiest things to master can be rolling out the dough.
The best way to ensure that you both have enough dough and don’t have too much scrap is by only making 10-20% more dough than the recipe needs. This way you will be sure that even after scraps, your dough will be the right thickness for the size it is rolled out to. Example: A recipe calls for 140g of dough to be rolled out, so make about 160g to account for scraps.
Another key to minimizing waste is by considering the shape of the final product. When rolling for a round pie or tart, the best thing to do is to start with a round piece of dough of an even thickness. This may mean playing with the dough a little, but as long as you work quickly, and don’t kneed it, it shouldn’t affect the final product.
Starting with your disk, make sure that both the table and the top of the dough are well floured. Every now and then, make sure that the dough is still lose from the table and well floured underneath, and that the rolling pin isn’t sticking to the top surface. For round dough, turn the dough often, after every roll or so of the pin, making sure that you’re rolling out the same distance on each roll, and working the dough back into shape lightly with your hands if necessary. When your dough looks to be roughly the right size, check the size of the pan by placing it on top, making sure to account for the height of the sides. No matter how carefully you made the pastry, it will still shrink a little in the oven if it’s not chilled first. Many pie shops freeze the fully assembled raw pies overnight before they are baked to reduce shrinkage.
For a square or rectangle the theory is the same, only you should start with a square or rectangle piece of dough of even thickness and rotate the dough 90º each roll. As for the thickness, the more even the pressure you rolled with, the more even the dough will be, but you can even it out a little at the end if it’s a little off. The best way to check if the dough is an even thickness throughout is to run the edges between your fingers, and roll out more where necessary.
It is important to note that if you start out with an irregularly shaped blob of dough, all that you`ll ever end up with is a larger, thinner blob.
