Preheat oven to 350°F (180°C), line a muffin pan with paper liners and set aside. Add 12 Oreos to a high speed food processor; blend until only fine crumbs remain. Add the melted butter and pulse until the mixture resembles wet sand.
Bake the cheesecakes in the oven for 12-15 minutes, or until the center is set and no longer jiggly. Remove from the oven and allow to cool for 30 minutes before placing into the fridge for 90 minutes to chill completely.