Pour apples into medium-sized bowl. Mix cinnamon, granulated sugar, and 1 T flour together and pour over apples. Stir until apples are coated. Pour into pie shell.
Over low heat, melt butter. Once butter is melted, add brown sugar and flour. Stir together.
Top with brown sugar butter crumble.
Bake at 375 for approximately 30 - 40 minutes or until rim of pie shell has browned.
Serve with ice cream.