Pour the apple pie filling into your crockpot. Sprinkle with 1/2 tsp cinnamon and mix in to combine.
Mix the remaining cinnamon in with the dry cake mix. Sprinkle over the apples. Drizzle the melted butter over the cake mix, evenly. Do NOT mix the butter into the cake mix.
Cover and Cook on high for 4 hours - or on low for 6 hours.
Serve with a scoop of vanilla ice cream, if desired.