Preheat the oven: Preheat your oven to 325°F (165°C). Line a 9×13-inch baking pan with parchment paper or lightly grease it to prevent sticking.
Make the crust and topping: In a large mixing bowl, beat 1 cup (225 g) softened unsalted butter, 1 cup (200 g) granulated sugar, and 3/4 cup (150 g) light brown sugar together until light and fluffy (about 2–3 minutes). Mix in 2 teaspoons vanilla extract. Gradually add 2 1/2 cups (315 g) all-purpose flour and 1/2 teaspoon salt, mixing until a crumbly dough forms.
Assemble the base layer: Press half of the dough evenly into the bottom of the prepared baking pan to form the crust. Bake for 15 minutes, or until lightly golden. Remove from the oven and let it cool slightly.
Prepare the caramel filling: While the crust cools, mix 1 jar (11 oz / 310 g) caramel sauce with 1/4 teaspoon sea salt in a small bowl. Adjust the salt level to your preference, adding more if you enjoy a stronger salty contrast.
Layer the caramel: Pour the salted caramel sauce evenly over the baked crust.
Add the topping: Crumble the remaining dough over the top of the caramel layer, covering it as evenly as possible for a balanced texture.
Bake the bars: Return the pan to the oven and bake for 25–30 minutes, or until the top is lightly golden and set. You want to see a firm top that has a slight bounce when gently touched.
Cool and serve: Allow the bars to cool completely in the pan before cutting into squares. For cleaner cuts, refrigerate the bars for 30 minutes before slicing. Enjoy these blissful bars with a side of nostalgia!