1. Preheat the oven to 350°F (175°C). Line a 9×13-inch baking pan with parchment paper, leaving an overhang on the long sides, and lightly grease the parchment and any exposed pan edges.

2. In a mixing bowl, whisk together the flour, granulated sugar, and salt for the crust until evenly combined.

3. Pour in the melted butter and vanilla extract, then stir until the mixture looks like soft, damp sand and starts to clump together with no dry flour remaining.

4. Transfer the crust mixture to the prepared pan and press it firmly and evenly into the bottom using your hands or the bottom of a measuring cup.

5. Bake the crust for about 15 minutes, or until the edges are just turning lightly golden and the surface looks set.

6. While the crust bakes, whisk the eggs in a large bowl until well blended.

7. Add the light corn syrup, brown sugar, melted butter, vanilla extract, salt, and flour to the eggs, whisking until the filling is completely smooth and glossy.

8. Fold in the chopped pecans until they are evenly coated and distributed throughout the filling.

9. When the crust comes out of the oven, give the pecan mixture a quick stir and pour it evenly over the hot crust, nudging the nuts into an even layer with a spatula.

10. Return the pan to the oven and bake for 22 to 28 minutes, or until the edges are set, the center is slightly puffed, and the filling only has a very slight jiggle when the pan is gently shaken.

11. Place the pan on a wire rack and let the bars cool completely to room temperature so the filling can firm up.

12. For the cleanest slices, chill the cooled pan in the refrigerator for about 1 hour, then use the parchment overhang to lift the slab out of the pan and cut into squares or rectangles with a sharp knife.