Line a large baking sheet (up to 11″ x 17″) with nonstick aluminum foil or heavy duty foil coated with nonstick spray, making sure it covers the bottom and sides of the pan.
Lay the crackers, edge to edge, in a single layer on the foil.
In a medium saucepan, heat the brown sugar, butter and salt, stirring frequently until the butter melts. Continue cooking and stirring for another 3 to 5 minutes, just until the mixture comes to a boil and starts to darken.
Remove the brown sugar mixture from the heat and stir in vanilla.
Pour the hot brown sugar mixture over the crackers, spreading evenly to coat them all.
Place the pan in the preheated oven for 5 minutes until the toffee is bubbly.
Remove the pan from the oven, quickly rearrange any crackers that may have shifted and allow to cool for exactly 1 minute.
Sprinkle the chocolate chips evenly over the toffee and crackers, and let stand for about 2 minutes until they begin melting.
Using a rubber scraper, butter knife or the back of a spoon, spread the chocolate chips to cover the entire layer of toffee and crackers.
Top with sprinkles or other desired toppings.
Let the candy cool to room temperature, then refrigerate for about 3 hours or until the candy is hardened.
Once set, peel away the foil and begin breaking the candy into snack-sized pieces by hand or with a knife.
Enjoy! Store candy in an airtight container in the fridge.