Preheat oven to 425°F.

Place pie crust in a 9-inch pie plate and crimp edges as desired. Chill until ready to fill.

Peel and core the apples, then slice into thin slices. I like using an apple peeler for this step. Place one inch of water in the bottom of a large pot. Add apples and cook, stirring occasionally, approximately 3-5 minutes after water boils, or just until the apples start to turn the slightest bit opaque.

Drain apples very well. Set aside to cool while making topping.

Make the crumble by combining the flour, brown sugar, oats, cinnamon and salt in a large bowl. Use a pastry cutter to cut in the butter until the mixture forms small crumbs.

Place apples in a large bowl. Toss with ¼ cup sugar and cinnamon. Transfer apples to prepared pie crust and top with crumble evenly.

Bake at 425°F for 15 minutes, then lower the oven temperature to 350°F and bake until crust is light golden, about 35-45 minutes.

Cool completely before slicing. Serve plain or with ice cream.

Store in refrigerator for up to 3 days. Pie can be frozen for up to 3 months.