Pie Crust: In a mixer fitted with a paddle attachment (or using a hand mixer), mix the flour, salt, and sugar for 1 minute. Add the butter and mix just until you have a crumbly, sandy mixture. You should still be able to see the pieces of butter. In a small bowl, stir the water and vinegar together. With the mixer running at medium speed, drizzle in the water-vinegar mixture and mix just until a dough forms. You should still see small bits of butter. Turn out onto a work surface, divide the dough in half, and shape into round, flat disks. Wrap separately in plastic wrap and refrigerate at least 30 minutes before using. (Or, refrigerate up to 48 hours or freeze up to 1 month before using. If frozen, let thaw in the refrigerator overnight before rolling out.)
When the time comes to roll out the dough, let the dough warm up for a few minutes at room temperature. Dust a work surface with just a few tablespoons of flour and keep some extra flour at hand. If you like, you can roll out the dough between 2 sheets of waxed paper (flouring the bottom sheet and the top of the dough before rolling), which makes it much easier to transfer to the pan later on. However, you won't be able to check the progress of the dough as easily. It's entirely up to you. Sprinkle a little flour on top of the dough and start rolling outward from the center with quick, light strokes. Don't worry if the edges split a bit; concentrate on forming a good circle from the center. Lift up and rotate the dough 1/4 turn every minute or so to help ensure even rolling. The dough should feel smooth and soft; some say it should feel like the inside of your forearm. If it gets sticky, sprinkle on a bit more flour, but don't do this more than 2 or 3 times; the dough will absorb too much flour. Instead, put it back in the refrigerator for 15 minutes to firm up the butter. Keep rolling until the circle is at least 2 inches larger than your pan (for example, 11 inches wide for a 9-inch pie pan), or 3 inches larger for deep-dish pies.
Set your pie or tart pan nearby. We always use heavy aluminum pans, because glass pans seem to bake the crust too fast. However, we know that the advantage of glass is that you can easily check the color of the crust. Again, it's up to you. Either choice will work. To transfer the crust to the pan, we find it easiest to roll a finished crust up onto the rolling pin, then gently unroll it in the pan. Or, you can fold it gently in quarters, lift it up, position the center point on the center of the pan, and unfold it into the pan. If using waxed paper, peel off the top layer, turn the crust gently into the pan, and peel off the remaining paper. Make sure that the dough is allowed to settle completely into the pan.
Don't stretch and press the dough into the corners; stretched dough will likely shrink back when you bake it. Instead, lift the edges of the crust to let it settle down into the corners. If the dough tears a bit, don't be concerned; we'll patch it in a minute. Using scissors or a sharp knife, trim the dough to within 3/4-inch of the rim. Use any extra scraps to patch the crust, pressing with your fingers (wet them if necessary) or set aside. Leave the edges of the bottom crust hanging over the rim.
Roll out the second piece of dough into a circle about 11 inches in diameter. Line a sheet pan with parchment or waxed paper. Roll the dough up onto the rolling pin, and then unroll it onto the sheet pan. Chill for 20 to 30 minutes before filling.
Preheat the oven to 425 degrees.
In a medium bowl, toss the apple slices, sugar, salt, cornstarch, cinnamon, nutmeg, and vanilla together. Transfer to the pie shell, and dot with the butter. Brush the overhanging edges of the dough with water. Carefully place the rolled-out top crust on top and pinch the edges together, turning under all around to make a thick edge. To decorate the rim, just press it all around with the back of a fork. For a slightly more advanced look, press the thumb and forefinger of one hand together. Use them to gently push the thick dough rim outward, while pushing inward with the forefinger of the other hand, so that they intersect in a "V" with the dough in between. Repeat all around the rim to make a wavy edge.
With the tips of a pair of scissors, snip 4 evenly spaced small vent holes in the top crust. Brush the top of the pie with cream, then sprinkle evenly with sugar.
Place the pie on a sheet pan to catch any juices that boil over. Bake in the center of the oven for 10 minutes, then reduce the heat to 375 degrees and bake until the crust is golden brown and the juices are bubbling at the vents, 40 to 50 minutes more. Check the pie after 30 minutes; if the crust is browning too quickly, cover lightly with foil. Let cool at least 30 minutes before serving. Serve warm or at room temperature.
Courtesy of Gale Gand, "Butter Sugar Flour Eggs" by Gale Gand, Rick Tramonto, Julia Moskin, Clarkson N. Potter Publishers, 1999