01 - Preheat oven to 350°F. Line a 10x15 inch rimmed baking sheet with aluminum foil and coat evenly 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.
03 - In a medium saucepan, melt the butter over medium heat. Add the brown sugar and salt, stirring constantly. Bring the mixture to a boil and continue stirring while it bubbles for 3 minutes. Remove from heat and stir in the vanilla extract.
04 - Immediately pour the hot toffee mixture over the arranged saltine crackers, using a spatula to spread it into an even layer.
05 - Bake in the preheated oven for 7 to 8 minutes, or until the toffee layer is bubbling across the entire surface.
06 - Remove the pan from the oven and immediately scatter the white chocolate chips in an even layer over the hot toffee. Allow them to sit for 2 minutes to soften, then gently spread the melted chocolate into a smooth, even coating across the entire surface.
07 - In a small bowl, combine the granulated sugar and ground cinnamon. Sprinkle the mixture evenly over the warm white chocolate layer.
08 - Allow the toffee to cool completely at room temperature for about 40 minutes, or refrigerate to speed up setting. Once fully set, break into 24 irregular pieces.