What a great alternative to the traditional apple pie! Be sure to use firm baking apples. Golden Delicious, Granny Smith, Jonathan, Jonagold, Rome, and Northern Spy are all good choices.
Preheat the oven to 425 degrees F. Fit the bottom crust into a 10-inch pie pan. Arrange the apples in the pie shell.
Mix the cornstarch with the apple juice in the top of a double boiler. Add the apple juice concentrate and cinnamon and cook until thickened, stirring constantly. Remove from the heat and pour over the apples. Cover the pie with the top crust. Cover the edges of the pie with aluminum foil to prevent browning. Place the pie on a baking sheet to catch any spills.
Bake for 25 minutes. Reduce the heat to 350 degrees F and bake for another 30 minutes. During the last 15 minutes of baking, remove the foil. Cool slightly before serving warm, or allow to cool completely.