Unwrap the Hershey Bars and break into squares. Set Aside. Remove two cups of marshmallows from the package and set aside. Spray a 9x13 inch baking dish with nonstick cooking spray or line with parchment paper.

Melt butter in a large skillet over medium heat. Add the package of marshmallows to the butter and continue to stir over medium-low heat until smooth. Remove from heat and stir the vanilla into the melted marshmallows.

Add the Rice Krispies and Golden Grahams to the marshmallow mix and stir to coat. Gently fold in 1 ½ cups of the reserved marshmallows.

Pour half of the marshmallow mixture to the prepared pan and spread to the edges in an even layer. Place ⅔ of the chocolate pieces evenly over the cereal. Top with the rest of the cereal mixture and gently press to form the treats.

Place the remaining ⅓ of the Hershey chocolate squares over the top of the treats as well as the remaining marshmallows. Lightly place a piece of wax paper over the treats and press the marshmallows into the warm treats.

Allow the treats to cool, then cut into bars and serve.