PREHEAT oven to 350˚F. LINE 13x9x2 inch baking dish with ALCAN® Non-Stick Baking Foil with the non-stick (dull) side facing up towards the food and the shiny side facing the dish; set aside.
ARRANGE apples evenly in dish. Sprinkle with cinnamon and sugar; set aside.
MIX flour, oats, brown sugar, walnuts and salt in a medium bowl. Cut in butter until well blended. SPRINKLE flour mixture over apples.
BAKE 40-45 minutes, until apples are soft and topping is lightly browned. Serve warm with ice cream.