Yogurt Pie Crust

Combine all-purpose flour, whole-wheat flour and salt in a food processor; pulse several times to blend. Add butter and process until the mixture resembles coarse meal, 8 to 10 seconds. Add yogurt and pulse until combined. With the motor running, add ice water, 1 tablespoon at a time, until the dough holds together without being sticky or crumbly. Divide the dough into 2 equal portions, shape into disks, and wrap each in plastic wrap. Refrigerate until firm, about 30 minutes or up to 3 days. Let stand at room temperature for 10 minutes before rolling.