In a small bowl, add butter, flour, oatmeal, sandwich cookies and ground cinnamon. Mix well to create a crumble. Add a small amount to each mason jar and tap jars lightly to settle.

Spoon cherry pie filling into each jar until almost full. Top with an additional tablespoon of crumble.

Place jars onto prepared baking sheet and bake for 20-25 minutes or until top is brown and filling begins to bubble. Let cool and serve warm.