Line 9x13" baking pan with foil and spray with cooking spray. Set aside.
In large bowl, melt marshmallows and butter in microwave.
Do this by heating for 1 minute and 30 seconds, then stir it and cook another 30 seconds, until it is all melted and smooth.
Stir in rice krispies and 1 1/2 cups of roughly crushed graham crackers.
Then stir in 1 cup of chocolate chips.
Spread evenly into prepared baking dish.
Let cool in refrigerator at least 15 minutes, ideally 30 minutes.
In medium bowl, melt remaining chocolate chips in microwave on 50% power in intervals of 30 seconds, stirring in between intervals, until smooth and melted.
Spread evenly over rice krispies. Sprinkle with remaining graham crackers and press lightly into chocolate so they stick.
Chill another 15-30 minutes, then enjoy!