The Crust: Prepare the gluten free pie crust, including baking for 10-12 minutes. Set aside. The Apple Filling: In a large bowl, toss together the apples, brown sugar, cornstarch, lemon juice, ground cinnamon, nutmeg and pure vanilla extract. Set aside while the oven preheats.
Preheat the oven to 375 degrees F.
The Crumble Topping: In a medium sized bowl, combine the rolled oats, almond flour, brown sugar and cinnamon. Now using a small spoon or rubber spatula, mix in the melted coconut oil (or applesauce). The mixture will be thick and crumbly.
Spoon all of the apple filling into the pie crust, but leave some of the juice in the bowl. This will help the pie not be too watery.
Now sprinkle the crumble topping onto the apples.
Bake for 45-55 minutes, until the top is golden brown and the apples have softened and thickened. Use a pie crust shield to prevent burning, or make one out of foil (link above to see how).
Let cool for 2-3 hours preferably before slicing and serving, as the time will allow the filling to thicken up quite a bit. Serve with non-dairy vanilla ice cream or coconut whip if desired.
Cover pie leftovers and store in the refrigerator for up to 4 or 5 days, if it lasts that long!