Preheat oven to 350°F (175°C). Line a 9x13-inch metal baking pan with parchment paper, leaving an overhang on the sides for easy removal later. Lightly butter or spray the paper.

In a medium mixing bowl, whisk together the melted butter, granulated sugar, light brown sugar, vanilla extract, and salt until completely combined.

Add the all-purpose flour and fold with a rubber spatula until a soft, crumbly dough forms. Press the dough evenly and firmly into the bottom of the prepared 9x13 pan.

Bake the shortbread crust for 18 to 20 minutes until lightly golden brown and firm to the touch. Remove from oven and set on a wire rack while preparing the filling.

In a medium saucepan set over medium heat, combine the cubed butter, dark brown sugar, pure maple syrup, and heavy cream.

Bring the mixture to a gentle boil, stirring frequently. Once bubbling, allow it to simmer for exactly 3 minutes to dissolve the brown sugar and emulsify the caramel base.

Remove saucepan from the heat. Immediately stir in the vanilla bean paste, cinnamon, salt, and chopped pecans, coating all nuts thoroughly in the glistening caramel glaze.

Pour the hot pecan caramel mixture evenly over the warm par-baked shortbread crust. Use a heatproof spatula to spread the pecans all the way to the edges of the pan.

Return the pan to the 350°F (175°C) oven and bake for 22 to 25 minutes, until the pecan filling is actively bubbling across the entire surface and the caramel has darkened to a rich amber hue.

Remove from the oven and immediately sprinkle the surface with flaky sea salt crystals.

Place the pan on a wire cooling rack and let it cool completely to room temperature (at least 2 hours). For clean, razor-sharp bakery squares, chill the pan in the refrigerator for 45 minutes before slicing.

Use the parchment paper overhang to lift the entire pecan pie bar block onto a cutting board. Using a large chef knife wiped clean between cuts, slice into 16 generous squares. Serve warm with vanilla ice cream or at room temperature!