Preheat the oven to 400°F and line a jelly roll pan with foil, placing saltine crackers in a single layer.

In a saucepan, combine brown sugar, butter, and salt. Cook on medium heat, stirring, until mixture boils and turns smooth, then remove from heat and add vanilla.

Pour the brown sugar mixture over the saltine crackers, spreading evenly.

Bake in the oven for 5 minutes until caramel is hot and bubbly.

Melt chocolate in a microwave-safe bowl in 30-second intervals, stirring until fully melted.

Remove baked crackers, cool for 1 minute, then pour melted chocolate over them and spread evenly.

Allow the crackers to cool to room temperature, then refrigerate to chill overnight.

Once cool, remove from pan, peeling foil away, and cut into snack-sized pieces.