Prepare the Crust:
Preheat the oven to 350°F (175°C).
In a mixing bowl, combine the flour, granulated sugar, and softened butter. Mix until the dough comes together.
Press the dough evenly into the bottom of a greased 9x13 inch baking pan.
Bake the crust for 20 minutes, or until lightly golden.
Prepare the Filling:
In a large mixing bowl, whisk together the eggs, corn syrup, granulated sugar, brown sugar, melted butter, and vanilla extract until well combined.
Stir in the chopped pecans.
Assemble and Bake:
Pour the filling over the pre-baked crust, spreading it evenly.
Return the pan to the oven and bake for an additional 30-35 minutes, or until the filling is set and golden brown.
Allow the bars to cool completely in the pan before cutting into squares.