Spray a 9x13 inch baking pan with nonstick spray and set aside.
In a large bowl, toss together cereal and chopped cookies. Set aside.
In another large, microwave-safe bowl, melt butter. Add the marshmallows, toss to coat, and microwave 3 minutes, stirring halfway through. Stir until marshmallows are completely melted.
Pour the marshmallow mixture into the cereal mixture and very quickly stir it all together with a rubber spatula until the marshmallow is evenly distributed.
Press into the prepared pan. Tip: Use a nonstick-sprayed piece of wax paper to press the mixture into the pan.
Place the chocolate chips in a microwave-safe bowl and microwave for 1 minute. Stir the chocolate chips, then return to the microwave for 30 seconds, remove and stir until melted. If they need to be heated longer, heat in 15-second intervals, stirring in between, until melted.
Pour the chocolate over the crispy treats and use a spatula to evenly distribute it.
Let cool completely, then cut and serve.
Recipe by Flying on Jess Fuel at https://www.jessfuel.com/thin-mint-rice-krispie-treats/