Making the Perfect Pie Crust: Close-Ups
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Make sure your fat is very cold, and that you cut it into manageable chunks before you tackle it with either a pastry cutter (as shown here) or with a food processor.
Here's what the mix should look like after you've almost finished cutting in the fat but before you add water. You should have a consistency like coarse cornmeal, with some chunks no larger than peas. I've got a little more cutting in to do here
Your dough should just hold together. Be very careful adding water or you'll end up with too soggy a dough. It's difficult to adjust things if you add too much water, so err on the side of dry.