Spray a 13x9-inch rectangular
or 15-inch oval baking dish
with cooking spray and pour the apple mixture into the dish. Spread the topping evenly over the fruit. Place the dish on a baking sheet (to catch any drippings) and bake in the oven until it is bubbly and the apples are tender, 55-60 minutes. Cool 10 minutes before serving. Serve with ice cream or whipped cream if desired.