Preheat your oven to 400°F (200°C).
Line a baking sheet with parchment paper and arrange the Saltine crackers in a single layer.
In a saucepan over medium heat, melt together unsalted butter and brown sugar, stirring continuously until it comes to a boil.
Pour the hot toffee mixture evenly over the arranged crackers and bake for about 5–7 minutes.
Remove from the oven and sprinkle semi-sweet chocolate chips over the hot toffee, spreading them out gently.
In a small bowl, combine granulated sugar and cinnamon, then sprinkle this mixture over the melted chocolate.
Add a light sprinkle of sea salt on top to enhance the flavors.
Allow to cool completely at room temperature before breaking into pieces.