With your rolling pin on a lightly floured surface, roll out the remaining dough ball to a 12-inch round. Fit into a 9-inch glass pie dish. Fold the overhanging dough under and crimp decoratively. Chill in the refrigerator for 15 minutes. If you’re using Pillsbury dough, which comes as two rolled-up rounds of dough in a box, each in a separate sleeve, roll out one round and place in a 9-inch glass pie dish.