01 - Preheat oven to 350°F. Line a rimmed baking sheet (9x13 inches) with parchment paper or aluminum foil and lightly grease the surface.
02 - Place saltine crackers in a single even layer across the entire baking sheet, covering it completely.
03 - In a medium saucepan, melt the butter over medium heat. Stir in the brown sugar, cinnamon, and salt. Bring to a boil and cook, stirring frequently, for 3 minutes until the mixture thickens and becomes bubbly.
04 - Carefully pour the hot toffee mixture evenly over the arranged crackers, using a spatula to spread and cover every cracker.
05 - Bake for 8 to 10 minutes until the toffee is bubbling across the surface and has turned a deep golden brown color. Remove from the oven.
06 - Immediately sprinkle the white chocolate chips or chopped chocolate over the hot toffee layer. Allow to sit for 2 minutes so the chocolate softens, then spread evenly with a spatula into a smooth layer.
07 - In a small bowl, mix together the granulated sugar and cinnamon. Sprinkle the mixture evenly over the melted white chocolate layer.
08 - Allow the toffee to cool completely at room temperature, then refrigerate for about 30 minutes until fully set and firm.
09 - Break into irregular pieces or cut into squares using a sharp knife. Serve immediately or store in an airtight container.