Prep the pan. Heat the oven to 350°F (175°C). Line a 9x13-inch baking pan with parchment, letting it overhang the long sides for easy lifting. Lightly spray the parchment.

Lay the graham crackers. Arrange full sheets snugly to cover the bottom of the pan. Break a few pieces if needed to fill gaps. Aim for a single, even layer.

Make the caramel. In a medium saucepan, combine butter and brown sugar over medium heat. Stir as the butter melts. Once it starts to bubble, let it simmer for 3 minutes, stirring occasionally, until thickened and glossy. Remove from heat and stir in vanilla and fine sea salt.

Pour and spread. Immediately pour the hot caramel over the graham crackers. Use an offset spatula to spread it evenly to the edges. Work quickly so it doesn’t set in one spot.

Bake briefly. Bake for 8–10 minutes. The caramel should be bubbling all over and slightly darkened at the edges. This step helps set the crunchy layer.

Add chocolate. Remove the pan from the oven and immediately sprinkle chocolate chips evenly over the hot caramel. Wait 2–3 minutes, then spread the softened chocolate into a smooth layer.

Add toppings. Sprinkle chopped nuts, flaky sea salt, or other toppings over the melted chocolate while it’s still soft so they stick.

Cool and set. Let the pan cool at room temperature for 20–30 minutes. Then transfer to the fridge for 1–2 hours until fully set and firm.

Slice or snap. Lift the slab out using the parchment. Cut into bars with a sharp knife or break into rustic pieces. Wipe the knife between cuts for clean edges.

Serve. Enjoy chilled for maximum snap or at room temperature for a slightly softer bite.