By hand in a bowl:
Stir both flours with the salt in a bowl. Add the butter, toss lightly into the flour with your fingers, and cut in the flour with a pastry cutter or a bench scraper for about 2 minutes, or until the pieces of butter are no larger than hazelnuts and no smaller than baby peas. Don’t worry if the pieces of butter aren't all the same size. Scrape off the dough that clings to the pastry cutter or bench scraper. Add the liquid and cut it in for 2 to 3 minutes, or until there is no loose flour in the bottom of the bowl and the dough looks like gravel. If the dough is still powdery, like grated Parmesan cheese, pinch a piece. If it doesn't come together, sprinkle in 2 more tablespoons of liquid and continue to cut in until the dough looks like gravel. Dump the dough onto a work surface. Use your fingertips to pinch it together until it starts to come together into a ragged mass; or smear the pastry dough with the heel of your hand, or, for flakier pastry, knead the dough just long enough to get it to hold together. Scrape up the pastry dough with a bench scraper. Flatten the dough into a disk if you’re using it for a pie or tart; roll it into a cylinder if you’re making cookies or tartlets. If you are not using the pastry dough right away, wrap it in plastic wrap and refrigerate.

By hand on a work surface:
Stir both flours with the salt in a pile on a work surface. Add the butter, toss lightly into the flour with your fingers, and cut into the flour with a pastry cutter or a bench scraper for about 2 minutes, or until the pieces are no larger than hazelnuts and no smaller than baby peas. Don’t worry if the pieces are different sizes. Scrape off the dough that clings to the pastry cutter or bench scraper. Make a well in the center of the pile with your fingers. Pour the liquid into the well. Combine the liquid and flour by gradually pulling the flour into the well with your fingertips. Cut the liquid into the pastry dough for about 3 minutes, or until it looks like gravel with no loose flour on the work surface. If the pastry remains powdery, like grated Parmesan cheese, pinch a piece. If it doesn't come together, sprinkle in 2 more tablespoons of liquid and continue cutting in until the pastry looks like gravel. Use your fingertips to pinch the dough together until it starts to come together into a ragged mass; or smear the pastry dough with the heel of your hand, or, for flakier pastry, knead the dough just long enough to get it to hold together. Scrape up the pastry dough with a bench scraper. Flatten the dough into a disk if you’re using it for a pie or tart; roll it into a cylinder if you’re making cookies or tartlets. If you’re not using it right away, wrap it in plastic wrap and refrigerate.

In a stand mixer:
A stand mixer has the advantage of not overheating the pastry dough, and unlike a food processor it leaves the butter in pieces so the pastry is flakier. But don’t start off at too high a speed or flour will fly around your kitchen! With the paddle attachment, mix both flours and the salt on slow speed for about 30 seconds. Add the butter and combine it with the flour on low to medium speed, for about 1 minute. Add the liquid and mix the dough on low to medium speed for 40 seconds to 2 minutes, or until it looks like gravel, depending on the temperature of the ingredients. lf it is still powdery and looks like grated Parmesan cheese after 2 minutes, pinch a piece to see if it comes together. If it falls apart, add 2 more tablespoons of liquid; if it holds together in a clump, continue mixing. If at any point the dough no longer feels cold, put the mixer bowl in the refrigerator or freezer for 15 minutes. Mix the dough on low to medium speed for 1 to 4 minutes, until it clumps together into a cohesive mass - you'll hear the motor straining. Flatten the dough into a disk if you’re using it for a pie or tart; roll it into a cylinder if you’re making cookies or tartlets. lf you’re not using the pastry dough right away, wrap it in plastic wrap and refrigerate.

In a food processor:
Making pastry dough in a food processor is by far the easiest method. The only disadvantage is that it mixes in the butter so completely that the dough is less flaky and more crumbly. Much is made about overworking dough in the food processor, but overheating it is more of a problem, because the food processor warms it very quickly. The secret is to chill all of the ingredients thoroughly before starting and, if need be, to chill the dough in the food processor bowl if it gets too warm while you’re making it. Combine both flours and the salt in a food processor and process for 15 seconds. With the processor off, add the butter and liquid, and process for 30 seconds. If the dough still looks powdery, like grated Parmesan cheese, pinch a piece. If it falls apart in your fingers, add 2 more tablespoons of liquid. Process for 15 seconds more. Feel the dough with the back of a finger. lf it’s no longer cold, put the entire work bowl in the freezer or refrigerator for 15 minutes. Dislodge any pastry dough sticking to the sides or bottom of the work bowl with a rubber spatula. Process for 10 to 30 seconds more, until the dough clumps together or clings to the sides of the food processor. Flatten the dough into a disk if you’re using it for a pie or tart; roll it into a cylinder if you’re making cookies or tartlets. lf you’re not using it right away, wrap it in plastic wrap and refrigerate.