To make apples: In a medium-size saucepan add apples, water, lemon juice, sugar and apple pie spice. Simmer over medium heat for 10-15 minutes just until softened. Set aside.
Preheat the oven to 350°F. Spray a 9 x 9 inch pan or similar, with cooking spray. Set aside.
In a medium-size mixing bowl, use a whisk to sift together oats, sugar, baking powder, cinnamon, salt and nuts.
In a separate bowl, whisk together, milk, butter, eggs and vanilla. Add to dry ingredients, using a spoon to mix until fully moistened. Mix in 1 cup cooked apples. (Keep remaining apples warm for serving)
Spread into prepared pan. Bake for 35-40 minutes or until set.
Serve immediately topped with remaining cooked apples drizzled with caramel or maple syrup or cream.