1. Preheat the oven to 400°F and line a rimmed baking sheet or 9×13-inch pan with parchment paper. Arrange the saltine crackers in a single even layer.

2. In a medium saucepan over medium heat, melt the butter with 1 cup granulated sugar and the salt, stirring until smooth.

3. Bring the mixture to a steady boil and cook for 3 to 4 minutes, stirring often, until thickened and slightly darker in color.

4. Remove from the heat and stir in the vanilla extract.

5. Carefully pour the hot toffee over the crackers and spread it quickly into an even layer.

6. Bake for 5 minutes, until the toffee is bubbling across the surface.

7. Remove from the oven and let it rest for 2 to 3 minutes.

8. Sprinkle the white chocolate chips over the hot toffee and let them soften, then spread into a smooth layer.

9. In a small bowl, mix 1/4 cup granulated sugar with the cinnamon and sprinkle it evenly over the white chocolate.

10. Cool slightly, then chill until firm. Break into pieces and serve.