Prepare your pie crust
Preheat your oven to 350 degrees F
In a medium bowl, mix corn syrup, sugar, butter, and vanilla - use a wooden spoon or electric mixer on low speed
Add eggs one at a time combining well between each
Add chopped pecans and combine well
You have 3 options with the pecan halves: 1. You can mix them in the filling with the chopped pecans; they usually rise to the top when the pie bakes. 2. You can place them on the bottom of the pie crust and then pour the filling over them, again, they usually rise to the top. 3. This is what I do: I pour the pie filling into the crust and then arrange the pecan halves in a pretty pattern and bake. Pour into prepared pie crust and bake for 60 minutes on center rack of oven
Check for doneness after 60 minutes by inserting a fork or toothpick (the original recipe said "a piece of clean straw") into the middle of the pie, if it comes out clean, it's done. If it's runny cook for 5-minute increments checking after each 5 minutes.
You can also check for doneness by thumping the middle of the pie. It should be puffed up and springy when it's done.