Step 1

Preheat the oven to 400℉. Line a 15 x 10-inch sheet pan with heavy-duty foil and generously coat with cooking spray. Cover the pan with an even layer of saltine or graham crackers. See note 2 for some tips before you get started.

Step 2

In a medium pot, combine the cubed butter and brown sugar. Set the pot over medium-low heat. Resist the urge to raise the temperature, even if it seems slow to start. Stir constantly with a silicone spatula, moving gently in one direction, until the mixture reaches a full boil. Once boiling, stop stirring and let it boil for exactly 3 minutes.

Step 3

After 3 minutes, remove the pot from heat and immediately pour the mixture evenly over the crackers. Use a spatula to spread it as needed; it doesn’t have to be perfect, as it will even out during baking.

Step 4

Bake for 5 minutes and then very carefully remove pan from oven. Let stand for 2 minutes and then sprinkle chocolate chips evenly over crackers. Let rest without touching for 5 minutes. Use a clean offset spatula to gently spread and coax the chocolate into an even layer. If adding toppings, sprinkle on immediately.

Step 5

Transfer pan to fridge and let chocolate harden for about 30 minutes, or freeze for 15 minutes. Remove from fridge, lift cracker from foil and break or chop into pieces.