In a microwave-safe bowl, place the marshmallows and butter. Heat on high for 1 minutes and stir vigorously. Heat again in 15 second increments, stirring after each time, until the marshmallows are completely melted.
Stir the food coloring into the marshmallow mixture until well blended.
To the bowl, add the cereal and oreos. Mix well.
Grab small handfuls of the treats and press into coal shapes. Allow to harden on wax paper.
Store in an airtight container.
Notes
Notes: If you do not have black food coloring, you can mix equal parts of blue, red, and green.You might have better results using your hands to mix the cereal and cookies into the marshmallow mixture.