Preheat oven to 400 degrees F. Line a baking sheet (bottom and sides) with foil.

Place the saltine crackers on your prepared baking sheet so that they cover the entrie tray in a single layer. You can break crackers if needed to fill in the edges.

In a medium saucepan, melt the butter over medium-high heat. Add brown sugar and stir until sugar is dissolved. Bring mixture to a boil, and allow to boil for 3 minutes without stirring. Pour mixture evenly over the crackers.

Place crackers in oven and bake for 5 minutes.

Carefully remove the baking sheet from the oven and immediately top with chocolate chips. Let chocolate chips sit for 2 minutes on the hot crackers. Using an offset spatula, spread chocolate over the top of the crackers so the toffee is completely covered.

Allow toffee to cool completely (the fridge helps). Break into pieces. Best served cold – at least I think so.