Preheat oven to 350 degrees. Place pie dough into pie pan and tuck or crimp edges with fork or fingers. Set aside.
In a large bowl whisk together sugar, cocoa powder, eggs, corn syrup, butter, and vanilla.
Add pecans and stir to coat.
Pour mixture into pie crust and bake for 50-55 minutes until set. (The center of pie should not jiggle & crust will be a golden brown.) Midway through cooking time if crust is golden brown place foil around edges of cooked crust or use a pie ring to keep the crust from browning to much.
Cool completely before cutting to allow filling to set up.
