01 - Preheat oven to 350°F. Line a 10x15 inch rimmed baking sheet with aluminum foil and coat generously with non-stick cooking spray.
02 - Lay the Saltine crackers in a single even layer across the bottom of the prepared baking sheet, covering the entire surface edge to edge.
03 - In a medium saucepan, melt the butter over medium heat. Stir in the brown sugar and salt, then bring the mixture to a rolling boil while stirring constantly. Let it bubble vigorously for 3 minutes. Remove from heat and stir in the vanilla extract.
04 - Immediately pour the hot toffee mixture over the arranged Saltine crackers. Use a spatula to spread it into an even, uniform layer.
05 - Place the baking sheet in the preheated oven and bake for 7 to 8 minutes, or until the toffee layer is bubbling across the entire surface.
06 - Remove from the oven and immediately scatter the white chocolate chips evenly over the hot toffee. Allow them to sit for 2 minutes until softened, then gently spread the melted chocolate into a smooth, even layer using a spatula.
07 - In a small bowl, combine the granulated sugar and ground cinnamon. Sprinkle the cinnamon sugar mixture evenly across the entire white chocolate surface.
08 - Let the toffee cool completely at room temperature for about 40 minutes, or refrigerate to speed up the setting process. Once fully set, break into 24 irregular pieces by hand or with a sharp knife.