In a medium bowl, whisk the three eggs until blended. Add the corn syrup, dark brown sugar, melted butter, and vanilla. and blend well. Stir in the pecans.
Pour into the pie shell.
Bake for 15 minutes at 425°, then reduce the temperature to 350°. Continue baking for 15-20 minutes or until the edges are set and the center jiggles slightly. Don't overbake!