Heat oven to 350°F and place a rack in the lower third.
Toast pecans on a sheet pan for 6–8 minutes until fragrant; cool. Roughly chop about 1¾ cups and reserve the rest as halves.
Whisk eggs in a large bowl until smoothly blended.
Whisk in brown sugar and granulated sugar until no streaks remain.
Stream in corn syrup and melted butter; whisk until glossy. Stir in vanilla, salt, and bourbon if using.
Fold the chopped pecans into the filling.
Set the pie crust in a pie plate if needed. Pour filling into the crust and arrange reserved pecan halves on top.
Shield the crust edge with foil. Bake 50–60 minutes, rotating once, until edges are set and the center jiggles slightly. Tent if browning too fast.
Cool on a rack at least 2 hours to fully set before slicing.