Transform the classic cake into an equally crowd-pleasing pie with a buttery crust and rich chocolate, pecan, and coconut filling.
Preheat oven to 375 degrees. Spread pecans in a single layer on a baking sheet, and if using, unsweetened coconut on another. Bake until pecans are fragrant and coconut is golden, 8 to 10 minutes for pecans and 5 to 7 minutes for coconut. Let cool. Coarsely chop pecans.
On a lightly floured surface, roll out dough to an 11-inch round about 1/8 inch thick. Transfer to a 9-inch pie dish; trim edges to a 1-inch overhang. Tuck edges under and crimp as desired. Freeze until firm, about 15 minutes.
Line crust with parchment and fill with dried beans or pie weights. Bake on lower rack until bottom no longer looks wet and edges begin to turn golden, about 30 minutes. Carefully remove parchment and beans; continue baking until golden brown all over, 10 to 15 minutes more. Let cool completely on a wire rack, about 30 minutes. Reduce oven temperature to 350 degrees.
Whisk butter into eggs, then whisk in condensed milk, vanilla, and salt. Stir in chocolate, sweetened coconut, and toasted pecans. Pour into cooled crust. Bake until just set in center, 30 to 35 minutes. Let cool on wire rack for 1 hour. Chill for at least 1 hour and up to 3 days. Serve, dolloped with whipped cream and sprinkled with toasted unsweetened coconut, if desired.