Prep a 9x13-inch baking dish by spraying with non-stick spray.  Set aside.

In a large bowl, mix cereal, chocolate chips and 2 1/2 cups mini-marshmallows.

In a microwave safe bowl, melt the butter and 3 cups marshmallows on 30% power for 30 second increments until melted.  Stir in between.  When fully melted, let mixture slightly cool.

Pour melted marshmallow mixture over the cereal mixture. Stir until evenly coated. Pour into the prepared pan and flatten with a greased spatula.

Break Hershey's squares in half. Press Hershey's squares and reserved 1/2 cup of mini marshmallows into the top of the cereal treats.  Use wax paper to press chocolate and mini-marshmallows over the top of the cereal mixture.

Allow treats to cool completely, then cut into squares and serve. Cover tightly and store any leftovers at room temp up to 5 days.