Layer one tube of biscuits in a slow cooker that has been sprayed with non-stick vegetable spray. In a small bowl, mix together brown sugar, cinnamon and butter just until combined; sprinkle half of mixture over biscuits.
Spread half of pie filling over top. Layer with remaining biscuits; sprinkle with remaining brown sugar mixture and top with remaining pie filling.
Cover and cook on high setting for 2 1/2 to 3 hours, until biscuits are golden.