Preheat oven to 400°F. Line a 9-inch pie plate with pie crust, trim edge to ½-inch, then flute.

Line pie crust with foil or parchment paper, then fill with pie weights or dried beans. Bake until lightly browned, 11-13 minutes. Remove foil and weights and bake 6 minutes more. Remove from oven and let cool while you work on the filling.

Reduce oven temperature to 350°F.

To a microwave-safe bowl, add chopped chocolate and 2 tablespoons butter. Microwave 1 minute, then stir. Continue microwaving in 30-second intervals until melted, stirring in between.

Let chocolate cool slightly, then whisk in sweetened condensed milk, 4 egg yolks, and vanilla. Add 1 cup pecans and stir to combine.

Pour into crust and bake until set, 15-20 minutes. Let cool 1 hour on wire rack.

While pie cools, make the topping:

Combine brown sugar, heavy cream, and ¼ cup butter in a saucepan over medium heat. Bring to a boil, stirring often. Once sugar has dissolved, remove from heat.

Add egg yolks to a small bowl, then add a small amount of the hot brown sugar mixture and whisk to combine. Add mixture back to saucepan, whisking constantly.

Cook again over medium heat until mixture thickens, stirring constantly, about 2-3 minutes.

Remove from heat and stir in coconut and vanilla. Let cool 10 minutes.

Pour cooled topping over filling, then sprinkle with pecans. Chill until cold, at least 4 hours. Slice, serve, and enjoy!