Line an 11 X 14 pan with Parchment paper, bottom and sides.
Place Saltine crackers in the bottom of the pan, and set aside.
Place the stick of butter in a non stick skillet, and turn the heat to medium.
When the butter begins to melt, pour the brown sugar in the pan, and add the granulated sugar.
When the butter melts, and the sugar's are dissolved, turn the heat up to Med-high, and bring the mixture to a soft boil.
When the mixture starts to bubble, turn off the heat, and pour the toffee mixture over the crackers, working quickly, and spread the mixture evenly with a knife.
Place the 11 X 14 pan in the oven for 7 minutes.
Remove the pan from the oven, and sprinkle the chocolate chips evenly over the toffee, letting them melt.
When the chocolate chips begin to melt, spread evenly over the toffee. (If the chocolate chips don't melt completely, place the pan back in the oven (with the oven off) for a couple of minutes, until the chocolate melts, and remove the pan and spread the chocolate to an even layer).
Sprinkle the M&M's over the melted chocolate, and place the pan in the freezer for about 30 minutes.
When the chocolate has completely set, and hardened, remove the pan from the freezer, and break the Christmas Crack into pieces.
Serve and Enjoy!
This will not stick to the parchment paper, and comes off easily. Some recipes call to line the pan with foil, but the toffee will stick to the foil, even if it's sprayed with cooking spray. Use the parchment paper for easy baking and removing.