Melt the candy coating in the microwave on 50% power for a few minutes until melted. (Note: It keeps its shape when melted - you can check with a fork) (Note2: Don't let any water get into it or it will seize up).
Pour marshmallows, cereal, pretzels, and peanuts into a bowl and mix well. Pour melted coating over mixture and stir until all is coated. Work quickly before the it cools.
Immediately add M&Ms and stir just until mixed. Don't stir too long or the M&Ms will melt.
Dump mixture out onto sheets of aluminum foil and spread with a spoon. When cool, break into pieces and store in an air-tight container.