Preheat oven to 350 degrees F. Grease 10x15 jelly roll pan with non-stick cooking spray; set aside.
In a large bowl, mix flour, sugar and salt. Cut in cold butter until mixture resembles pea sized crumbs. Press into a prepared jelly roll pan.
Bake 20 minutes, until the edges are lightly golden brown.
For the pecan filling, whisk the eggs in a large bowl. Once whisked add the corn syrup, sugar, melted butter and vanilla. Stir in pecans.
Spread filling over the hot crust.
Bake 25-30 minutes longer or until filling is set (you might want to place another pan under your bars in case some of the liquid spills over).
Cool completely in pan on a wire rack. Cut into bars.
Serve & enjoy!