Apple-butterscotch pie

Preheat the oven to 375 degrees .
In a small saucepan, stir 3/4 cup of the brown sugar and
the half-and-half over medium heat until the sugar dissolves.
Remove from the heat and add the butter and the vanilla.
Stir until the butter melts. Set the butterscotch mixture aside to cool completely.
In a medium bowl, toss the apples with the lemon juice.
Add the remaining 1/4 cup brown sugar, the cornstarch, lemon zest,
and the orange zest (if using), cinnamon, allspice and nutmeg.
On a lightly floured work surface, roll out the larger disk of dough into a
13-inch round about 1/8 inch thick. Fold the dough in half.
Transfer to a 9-inch pie pan, and gently unfold the dough to fit into the pan.
Sprinkle the bottom of the dough with the flour.
Fill the pie pan with the apple mixture.
Pour the cooled butterscotch mixture over the apples.
On a lightly floured work surface, roll out the remaining pie dough into
a 10- to 11-inch round about 1/8 inch thick.
Fold the dough in half, and gently unfold over the apples to cover the filling.
Using scissors or a sharp knife, trim the edges of the 2 pie crusts to a 1-inch overhang.
Pinching the 2 crusts together, fold the dough under itself so the edge of
the fold is flush with the edge of the pie pan.
Flute the crust around the edges of the pan.
Cut a few slits in the top crust so the steam can escape.
Bake until golden brown and the juices are bubbling (look into the slits to check), about 45 minutes.
Cool completely on a wire cake rack.