Line an 8x8 square baking pan with parchment paper and spray with non-stick cooking spray.
In a large bowl, combine dry cookie mix, cold cubed butter and apple chips. Use your hands or a pastry cutter to blend ingredients together until the apple chips are crushed and only small pieces of butter remain. Add cold water and mix into a dough. Shape dough into a flat disc and cover in plastic. Chill 10 minutes or until firm.
In a medium sized bowl, combine all ingredients for the streusel topping. Use your hands to fully incorporate the butter into the mixture until it becomes crumbly.
Preheat oven to 350 degrees. Unwrap dough and press into the bottom of the prepared pan. Spread applesauce evenly over the top of dough. Sprinkle streusel topping evenly over applesauce.
Bake 30-35 minutes, until golden around the edges and set in the middle. Cool completely on a wire rack. Lift parchment to remove bars from pan once cooled, then cut into squares!