Line a 9.5" X 13" sheet with parchment paper and place graham crackers in single layer on the paper.

Place marshmallows in a large, microwave safe bowl and pour the melted butter over them. Stir to coat the marshmallows. Microwave in 30 second intervals until marshmallows are completely melted.

Spray a spatula with non-stick cooking spray, or rub with butter, then use it to spread the melted marshmallows evenly over the graham crackers.

Melt the chocolate in the microwave, stirring every 30 seconds until melted and smooth.

Spread the chocolate evenly over the marshmallow layer.

Place pan in refrigerator to chill for 30 minutes, or until chocolate is hard.

Remove from refrigerator and use sharp knife to cut the bark into pieces.

Enjoy!