01 -
Preheat oven to 350°F (175°C).
02 -
In a large mixing bowl, combine sliced apples with granulated sugar, ground cinnamon, and lemon juice. Toss to coat evenly.
03 -
Sprinkle 1/4 cup all-purpose flour over the apple mixture and mix until apples are well coated.
04 -
In a separate bowl, mix 1 cup all-purpose flour, rolled oats, packed brown sugar, and cold unsalted butter. Use a pastry cutter or your fingers to incorporate the butter until the mixture is crumbly.
05 -
Arrange the apple filling evenly in the prepared pie crust. Spread the crumb topping over the apples, covering completely.
06 -
Place the pie on the center rack and bake for 45 to 50 minutes, or until the crumb topping is golden brown and apples are tender.