Prepare Your Workspace:

1. Preheat oven to 400°F (200°C).
2. Line a rimmed baking sheet with parchment or foil, letting it hang over the edges.
3. Lightly spray or butter the lining to prevent sticking.

Arrange the Crackers:

1. Lay saltine crackers in a tightly packed single layer.
2. Break crackers to fill any gaps.
3. Make sure the entire sheet is fully covered.

Create the Toffee:

1. Combine butter and dark brown sugar in a heavy saucepan over medium heat.
2. Stir until butter melts and mixture blends.
3. Let bubble and continue stirring 3–4 minutes until thick, rich, and caramel colored.
4. Remove from heat and stir in vanilla and fine sea salt.

Pour and Spread:

1. Quickly pour hot toffee over crackers.
2. Spread to edges so all crackers are coated.

Bake to Perfection:

1. Bake 5–7 minutes until toffee bubbles across the entire surface.
2. Watch closely to avoid burning.

Add the Chocolate:

1. Remove from oven and sprinkle chocolate chips over the hot toffee.
2. Let sit 3–4 minutes to melt.
3. Spread into a smooth, even layer.

Garnish Generously:

1. Sprinkle toasted pecans over warm chocolate and press lightly.
2. Add flaky sea salt and optional toffee bits.

Cool Completely:

1. Cool at room temperature for 30 minutes.
2. Refrigerate 1–2 hours until toffee and chocolate are fully set.

Break into Pieces:

1. Lift sheet out using parchment overhang.
2. Break into pieces by hand or cut into squares with a sharp knife.