Grease a large mixing bowl with butter, then pour in the Rice Krispies Cereal, and set aside.
Cut the butter into slices and place them in a large saucepan.
Set the pan over LOW heat and allow the butter to begin melting.
Add the marshmallows and toss to coat.
Stir the marshmallows occasionally until about 75% have melted. This should take 7-10 minutes.
Remove the partially melted marshmallows from the stove and stir until melted and smooth.
Alternatively, you can melt the marshmallows in the microwave on high power for 1 minute, then let the bowl rest in the microwave for a minute or two. Remove the bowl, and stir until melted. Heat for additional 15-second increments, stirring after each, if needed.
Stir in 1 teaspoon of liquid green food coloring or mix in several drops of green gel coloring.
Pour the marshmallows over the cereal and toss to coat.
Let the cereal treat mixture cool for about 5 minutes until it's easy to handle.
Scoop out 15 hand fulls of the cereal treat mixture and roll them into balls.
Shape them into wreaths by creating a hole in the center and flattening the treats slightly.
Attach three sets of 3 red mini M&M's around the wreath. If needed use melted candy melts, clear piping gel, or corn syrup to get them to stick.
Then, attach one modeling chocolate or fondant bow to each wreath.
Store these marshmallow treats in an airtight container at room temperature for up to 5 days.