Step 1

Spray the insert of a 4-quart slow cooker liberally with cooking spray. Cut a piece of parchment paper to fit the cooker and lay it in the bottom.

Step 2

Using an electric mixer, briefly beat cake mix with the eggs then the butter and the sour cream until smooth. Add the milk gradually and continue to beat for 2-3 minutes on medium high. Stir in spices.

Step 3

Cut or crush apple pie filling to make smaller pieces, stir in the brown sugar and cinnamon. Spoon half the mixture in an even layer on the bottom of the slow cooker and top with half the cake batter. Spoon the remaining apple layer on top and finish with the remaining batter, smoothing it evenly on top.

Step 4

Cover and cook on high for 2 1/2 hours. Remove the insert (if possible) and remove the lid so cake cools for 15 minutes, then invert onto serving platter. Remove the parchment paper and serve the coffee cake while still slightly warm.