Preheat oven to 350°. Line a 15 x 10 jelly roll pan with aluminum foil.
Fill the entire bottom of the pan with crackers, placing them side by side but not overlapping. Set aside.
Add the brown sugar and butter to a medium saucepan. Place on medium heat, stirring continually until the butter melts, until a low boil begins. Boil for 2-3 minutes.**
Remove from heat and allow to cool for one minute. Pour over the top of the crackers.
Place pan in the oven and bake for 5 minutes.
Remove from oven and sprinkle chocolate chips on top of the crackers. Return to oven and bake for an additional 4-5 minutes or until the chocolate chips have melted.
Immediately sprinkle with the mini marshmallow bits, M&M candies and sprinkles.
Place in refrigerator for 30 minutes to allow the chocolate to cool and harden.
Before serving, cut or break into squares.
**Be sure to watch the brown sugar and butter mixture carefully as it boils to make sure that it doesn't burn!If you own a candy thermometer you can use it to melt your butter and brown sugar. Melt your butter then add the brown sugar. Bring to a low boil without stirring and boil until a candy thermometer reads 225 degrees or a drop forms a hard ball in ice water.