Be sure oven temperature is set to 350°F and the oven rack is adjusted to the middle position.
Melt the butter in a medium saucepan set over medium heat.
6 tablespoons unsalted butter
Add sugars and cook (stirring often) until mixture starts bubbling about 3-4 minutes. Add corn syrup and cook (stirring often) until mixture comes to a boil, about 3-4 minutes.
1 cup granulated sugar, 1⅛ cups light corn syrup, 2 tablespoons dark brown sugar
Remove the mixture from the heat and cool 5 minutes.
Add the eggs to a medium heatproof bowl and whisk lightly. Pour 1 cup of the slightly cooled sugar mixture into a heatproof measuring cup.
4 large eggs
Very slowly whisk the 1 cup sugar mixture into the beaten eggs then very slowly whisk the beaten egg/sugar mixture back into the hot sugar mixture in the saucepan. Quickly whisk the mixture until thoroughly incorporated.
Add vanilla and salt and whisk to incorporate.
1 teaspoon pure vanilla extract, 1 teaspoon kosher salt
Add the pecans and stir well.
2 cups chopped pecans
Pour the filling into the cooled crust and bake at 350°F for 30 minutes. If the crust is browning too quickly, cover the pie crust edge with a pie crust shield or foil. Bake an additional 20-30 minutes or until the pie is almost set in the middle. The pie should be barely jiggly in the middle.
Transfer the pie to a cooling rack to cool completely before serving, at least 3 hours.
Serve with a scoop of ice cream or lightly sweetened whipped cream, if desired.