Preheat oven to 350°. In a small bowl cut butter into cake mix until crumbly. Press into a well-greased 13x9-in. baking pan. Bake 15-18 minutes or until lightly browned.
Meanwhile, in a large bowl, beat cream cheese, 1/2 cup sugar and vanilla until smooth. Add eggs; beat on low speed just until combined. Spread over crust.
Spoon apple pie filling over cream cheese layer. In another bowl, mix flour, brown sugar and oats; cut in butter until crumbly. Sprinkle over apple layer.
Bake 25-30 minutes or until filling is set. Drizzle with Salted caramel topping; cool in pan on a wire rack 1 hour. Refrigerate at least 2 hours. Cut into bars. Yield: 3 dozen.