First mix the melted butter and graham cracker crumbs together. (I like to toss into my food processor and pulse until combined).
Press the mixture into 9x13 baking dish that is lined with parchment paper.
Then pour the sweetened condensed milk over the graham cracker crumb mixture.
Next sprinkle the coconut and chocolate chips evenly over the sweetened condensed milk.
Top with the red and green M&M's.
Bake at 350 degrees F for about 25 minutes, or until the edges start to turn golden brown.
Cool for at least 1 hour, then cut into bars.