Preheat Oven:
Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or foil and arrange saltine crackers in a single layer.

Make Caramel Sauce:
In a saucepan over medium heat, melt butter and brown sugar. Stir constantly and bring to a gentle boil. Simmer for 3 minutes, then remove from heat and stir in vanilla.

Pour and Bake:
Pour the caramel mixture evenly over the saltines. Spread with a spatula to cover all crackers. Bake in the oven for 5 minutes.

Optional Topping:
Remove from oven and sprinkle chocolate chips on top while hot. Let sit for 2 minutes, then spread melted chocolate evenly. Sprinkle sea salt if desired.

Cool and Break:
Let cool completely at room temperature or refrigerate until firm. Break into pieces and serve.