Food processors are absolutely fabulous for taking all the pain out of the production of pie crust dough. For one crust, put about 3/4 cup unbleached all purpose flour and 3/4 cup pastry flour (I use wheat) in food processor bowl. Add a pinch of salt and, if making for a dessert, a tablespoon of sugar (if desired). Blend for a second to mix. Cut one stick of cold or frozen butter into 10 or more pieces and blend in pulses until the mixture resembles fine cornmeal. Add the yolk of one egg and blend until the mixture balls up (or until you can manually ball it up yourself - it may or may not ball up depending on humidity, etc.). You may need to scrape the sides down once when blending the egg. If it doesn't look like it's going to ball up, add a tablespoon of cold water. Turn the dough out onto a square of wax paper, form into a disc, and refrigerate 20-30 minutes. When it's chilled a bit, take it out of the fridge, open up the wax paper and flatten it out, and then add another piece of wax paper on top and roll the dough out. The wax paper should keep the dough from sticking, and it eases transfer to the pie tin. Just carefully remove the bottom side of the wax paper first (it's usually more crinkled than the top sheet), and then transfer to the tin and carefully peel the other sheet of wax paper off before molding the dough to the tin. It's a piece of cake, so to speak, and the results are so much more yummy than store-bought crusts!