Once you have your dough all prepared, roll the dough into 2 rounds, 1/8-inch thick, on a lightly floured surface. Use 1 to line the bottom of a 9-inch pie pan. Roll up the second round between 2 pieces of wax paper and refrigerate along with the pie shell. In a small bowl, combine ½ cup light brown sugar, 2 tablespoons flour, 1 teaspoon cinnamon and 1 teaspoon freshly grated nutmeg. Now grab 6 or 7 apples—remember, make sure they’re the crisp and tart kind, such as a Granny Smith or a Pippin—and peel, core and quarter each apple. Now cut each apple quarter into 4 slices. In a large bowl, toss the apples with the juice of 1 orange. Combine the brown sugar mixture with the apples. Toss to coat. Let the apples stand, at room temperature, for 1 hour.
Preheat the oven to 450 degrees. Using a slotted spoon, fill the pie shell with the apples. They should rise at least 1 inch above the rim. Discard the liquid that collects in the bottom of the apple bowl. Dot the apples with unsalted butter—around 2 tablespoons. Moisten the rim of the bottom crust with water and cover with the second round of dough, crimping the top to the bottom with your fingers or a serving fork. Cut 4 symmetrical slits in the top crust.
Now bake in the preheated oven for 15 minutes. Reduce the heat to 350 degrees and bake for an additional 30 minutes more. This pie does not improve with age, but it can be prepared 1 day ahead. Store at room temperature. Reheat in a 250-degree oven.