Preheat the oven to 400° F.
In a large mixing bowl, combine the cherries, cornstarch, and ¼ cup sugar, stirring well to mix. Set aside.
Unfold one pie crust and place in a 9-inch pie plate.
Add the cherry mixture, then brush the rim of the pie crust with water. This seals the crusts together.
Unfold the second pie crust over the top of the pie.
Run a knife around the edge of the pie plate to cut off the excess dough and make the edge of the crust flush with the pie plate.
With the tines of a fork, press down around the top rim edge of the pie—this makes for a nice decorative edge as well as seals the crusts together.
Sprinkle the top with the remaining sugar.
Cut four small slits in the top crust for air vents.
Place the pie plate on a cookie sheet in the oven and bake for 20 minutes.
Lower the oven temperature to 350° F and continue baking the pie for another 40 minutes.
Let cool on a wire rack before serving.