Prep the pan and crackers. Line a rimmed baking sheet with parchment paper or heavy-duty foil, leaving overhang for easy lifting. Arrange the Club crackers in a single layer to cover the entire surface. Set aside.

Heat the oven. Preheat to 350°F (175°C). You’ll briefly bake the caramel-coated crackers to set the toffee.

Make the caramel. In a medium saucepan over medium heat, melt the butter. Stir in the brown sugar and bring to a gentle boil, stirring often. Once it reaches a steady boil, cook for 3–4 minutes, stirring constantly, until smooth, glossy, and slightly thickened.

Finish the caramel. Remove from heat. Stir in vanilla and salt. The mixture will bubble, so be careful.

Coat the crackers. Immediately pour the hot caramel evenly over the crackers. Use an offset spatula to spread it to the edges and fill any gaps.

Bake to set. Place the pan in the oven for 5–7 minutes, until the caramel is bubbling all over. This helps the caramel soak into the crackers and set properly.

Add the chocolate. Remove the pan from the oven and immediately sprinkle the chocolate chips evenly over the hot caramel. Let sit for 2–3 minutes to melt, then spread into a smooth layer.

Add toppings. While the chocolate is still soft, sprinkle on nuts, flaky salt, or your favorite add-ins. Press lightly so they stick.

Cool and set. Let the pan cool at room temperature for 30–45 minutes, then refrigerate for 1–2 hours until the chocolate is firm.

Break and serve. Lift the toffee from the pan using the parchment or foil. Break into irregular pieces. Serve chilled for extra snap or at room temperature for a slightly softer bite.