Pecan-Brownie Pie

Name: Pecan-Brownie Pie
Prep time: 25 min
Total time: 25 min
Cuisine: American, Southern
Ingredients: 1 tbsp. all-purpose flour, plus more for work surface; 1/2 recipe Basic Pie Dough; 3/4 c. (1 1/2 sticks) unsalted butter; 6 oz. bittersweet chocolate (60 percent), chopped; 3/4 c. packed dark brown sugar; 1/2 c. granulated sugar; 1/2 tsp. kosher salt; 3 large eggs, lightly beaten; 3 tbsp. heavy cream; 1 tsp. pure vanilla extract; 1 1/2 c. pecan halves, coarsely chopped and toasted, plus 1/2 cup whole, divided; Ice cream or whipped cream, for serving