Instructions

Adjust oven rack to lower-middle position and heat oven to 375 degrees. Roll 1 single-crust pie dough into 12-inch circle on lightly floured counter. Loosely roll dough around rolling pin and gently unroll it onto 9-inch pie plate, letting excess dough hang over edge. Ease dough into plate by gently lifting edge of dough with 1 hand while pressing into plate bottom with your other hand. Leave any dough that overhangs plate in place. Trim overhang to ½ inch beyond lip of pie plate. Tuck overhang under itself; folded edge should be flush with edge of pie plate. Crimp dough evenly around edge of pie using your fingers. Wrap dough-lined pie plate loosely in plastic wrap and place in freezer until dough is fully chilled and firm, about 15 minutes.
Line chilled pie shell with two 12-inch squares of parchment paper, letting parchment lie over edges of dough, and fill with pie weights. Bake until lightly golden around edges, 18 to 25 minutes. Carefully remove parchment and weights, rotate pie shell, and continue to bake until center begins to look opaque and slightly drier, 3 to 6 minutes. Let cool completely.
Reduce oven to 325 degrees. Combine ⅔ cup semisweet chocolate chips and 4 tablespoons unsalted butter in bowl and microwave at 50 percent power, stirring often, until melted, about 90 seconds. Whisk in ¼ cup vegetable oil and 2 tablespoons unsweetened cocoa powder until smooth.
In separate bowl, whisk ¾ cup packed (5¼ ounces) dark brown sugar, 2 large eggs, 1 tablespoon vanilla, and ¾ teaspoon table salt together until smooth. Whisk chocolate mixture into sugar mixture until incorporated. Stir in ¼ cup (1¼ ounces) all-purpose flour and remaining ⅓ cup chocolate chips until just combined.
Spread 1¼ cups pecans, toasted and chopped coarse in bottom of pie shell, then pour batter over top, using spatula to level. Bake pie until toothpick inserted in center comes out with thin coating of batter attached, 30 to 35 minutes. Let pie cool on wire rack until barely warm, about 1½ hours. Serve. (Pie can be reheated, uncovered, in a 300 degree oven until warm throughout, 10 to 15 minutes.)