Lay a single layer of graham crackers out on onto the prepared baking sheet, feel free to cut crackers in half to fit into tight corners.
In a medium saucepan, combine butter, sugar, vanilla and salt. Cook over medium heat, whisking constantly, until butter has melted and mixture is light brown in color, about 10-15 minutes.
Immediately spread the hot mixture evenly over the graham crackers. Sprinkle with chocolate chips. Let sit for 1-2 minutes. After 1-2 minutes, spread the chocolate in an even layer until smooth. Drizzle frosting to decorate and top with M&M's.
Let cool about an hour. Then break into pieces and serve.