Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan or line with parchment paper.
In a large bowl, cream together butter, granulated sugar, and salt until smooth.
Mix in the flour until a dough forms. Press the dough evenly into the prepared pan.
Bake for 15 minutes or until lightly golden. Remove from the oven and set aside.
In a saucepan over medium heat, combine brown sugar and heavy cream. Bring to a gentle boil and cook for 2-3 minutes, stirring constantly.
Remove from heat and stir in pecans and vanilla extract. Pour the caramel pecan mixture evenly over the baked crust.
Bake for an additional 20-25 minutes, or until the caramel is bubbling and set.
Allow to cool completely before slicing into bars.