Preheat your oven to 400 degrees. Line a lipped baking sheet with tin foil and generously spray with non-stick spray. Set aside.
Line your crackers in the pan, leaving a little space between each one.
In a large sauce pan, over medium heat, add the butter and brown sugar and bring to a boil, stirring to break it up. Once it starts to boil, leave it alone for about 3 minutes, without stirring. Pour the boiling mixture over the crackers and bake for 5 minutes.
While the toffee is baking, melt the peanut butter in the microwave (it will probably only take about 30 seconds, stir, maybe another 15-20 seconds).
Remove the pan from the oven and pour the peanut butter on top (the toffee will be bubbly; I had to "dunk" some of the crackers under the toffee & straighten them back up before I poured the peanut butter on top). Smooth it into an even layer with a spatula.
Evenly sprinkle on the chocolate chips and put the pan back in the oven for 1 minute.
Remove the pan from the oven and smooth the chocolate chips into the melted peanut butter into one smooth layer.
Sprinkle with various sprinkles. I made strips of different colors/shapes so when I broke it up, there was a variety.
Put the entire pan in either the freezer for at least an hour or the fridge for two hours.
Once cold and set, break up the toffee into random sized pieces.
Store in an airtight container for up to 10 days. I like it cold, so I keep it in the fridge.