Preheat oven to 400 degrees. Line a large rimmed cookie sheet with foil. Spray foil with cooking spray. Line crackers in a single layer.
In a medium sauce pan, combine butter and brown sugar. Bring to a boil and boil for 3 minutes. Immediately pour evenly over the crackers. (Make sure to cover each cracker)
Place in oven and bake for 5 minutes. Remove from oven, and sprinkle with chocolate chips. Let stand a couple minutes, and then spread melted chocolate evenly over the toffee. Sprinkle with crushed candy canes and/or sprinkles.
Let cool completely and then cut into squares. Enjoy!