Preheat the oven to 425 degrees F.
Start by making the crust. In a large mixing bowl, mix the dry ingredients together. In another bowl, mix the oil and water together with a whisk.
Add the oil and water mixture to the dry ingredients. Mix until the dough holds together. Add a bit more water if needed. Press the dough into a 9-inch pie plate. Set aside.
For the filling, in a large bowl, combine all filling ingredients. Let stand for 15 minutes. Stir and then spoon the filling into the prepared pie crust.
Bake at 425 F for 15 minutes then lower the heat to 350 F and bake 40 minutes, or until the apples are tender.
Sprinkle with chopped walnuts if you choose.