Bring pie crust to room temperature by putting it out on the counter for about 15 minutes.
Preheat oven to 350.
In a small saucepan, melt the butter over medium heat. Once butter is melted, continue to cook it over medium heat until it turns golden brown. Remove from heat and set aside.
Grease a 9-inch pie pan and press the thawed pie crust into the pan.
Pour the chopped pecans evenly over the pie crust.
In a large bowl, mix eggs, Karo syrup, brown sugar, vanilla, salt, and cinnamon. Stir until combined. Add browned butter.
Pour the mixture evenly over the pecans.
Bake for 40-50 minutes, or until filling has set up. If the crust looks like it's cooking too fast, cover it with foil.
Let cool completely before serving. Serve with whipped cream.