In a large bowl or standing mixer combine the flour, 1/2 cup of sugar, 1/2 teaspoon of salt and 2 sticks of butter, mix well. Mixture will be dry and crumbly. In a large pan, preferrably 10x15, grease bottom of pan or I prefer to use parchment paper to line. Pour crust mixture onto greased pan and press firmly to create a crust. Bake crust in oven for 10 minutes at 350 degrees.
In a separate bowl, or standing mixer with bowl, combine eggs, corn syrup, sugar, brown sugar, melted butter, vanilla extract and chopped pecans, mix well. Set aside until crust is done baking.
When crust is done baking, pour prepared pecan filling mixture on top of hot crust, use a spatula or spoon to distribute evenly. Place back in the oven and bake for 35 minutes at 350 degrees. Let cool, then serve.