If you've never made pastry dough in the food processor, you're in for a treat. This recipe is foolproof and easy. Make sure all the ingredients are chilled, plop them into the processor, and that's it. You'll get flaky, manageable dough.
Measure the flour into the processor with the regular blade attached. Add the unsalted butter, cut into cubes, and lard, cut into cubes. (Your fat should be frozen or very cold). Add salt. Pulse three times with three counts per pulse to lightly mix the ingredients.
With the motor running, pour ice water into the work bowl just until the dough starts to get noticeably crumbly. Don't wait until it is a big clump or it will be way too wet and will turn out tough.
Stop the machine, dump the crumbly dough into a bowl, and gather the dough into a ball with your hands. You can squeeze it a bit to make it stick together. If it just won't form a ball, add a tiny bit more water. (Note that if you are making crust in the food processor, you will use less water than most recipes call for).
Wrap your dough ball in plastic wrap and chill it about 30 minutes in the refrigerator. Roll it out on a cool surface if you can. Then follow your pie recipe for baking.