Spray 4 or 5 quart slow cooker with cooking spray. Place apples evenly in bottom.
In medium bowl, stir flour, granulated sugar, baking soda, salt, and pumpkin pie spice until well mixed. Add in the water, molasses and oil to the flour and stir until just until moistened.
Spread the batter evenly over the apples in the slow cooker. Sprinkle the entire mix with brown sugar.
In a microwavable measuring cup, mix apple cider and margarine. Microwave uncovered on High 1 to 2 minutes or until margarine is melted. Pour over mixture in slow cooker.
Cover and cook on High heat setting 2 to 2½ hours or until toothpick inserted in center comes out clean. Turn off slow cooker; uncover. Let stand 15 minutes. Serve warm.
Gluten Free
Substitute your favorite gluten free flour blend for the flour.