Preheat the oven to 400℉. Line a baking sheet with aluminum foil and lightly spray with cooking spray.
Place the saltine crackers on top of the baking sheet in a single layer. Set aside.
In a medium saucepan, melt the butter and brown sugar. Bring to a boil and allow to boil for 3 minutes. Do not stir while it is boiling!
Immediately pour over the crackers and spread until the crackers are completely coated.
Bake in the preheated oven for 5 minutes.
Remove from the oven and top with the chocolate chips. Let it sit for 5 minutes. Spread the chocolate over the crackers and top with the chopped pecans. Allow to cool completely before breaking into pieces.