Chocolate-Sesame Crust
In a small saucepan over low heat, add the butter and brown sugar, stirring to dissolve the sugar until the butter has melted.
Meanwhile, grind the sesame seeds in a spice mill or with mortar and pestle
Pulse the cookies in a food processor until finely ground
Pour butter mixture into the food processor; add the sea salt and ground sesame seeds. Pulse to combine.
Using a measuring cup, press cookie mixture firmly onto bottom and up the sides of a 9" pie pan. Freeze until very cold (~ 20–25 minutes)
Preheat oven to 350° F
Bake the crust until firm and slightly darkened in color (~ 15–18 minutes). If crust slides down sides, gently press it back up.
Let cool.
** Do Ahead: The crust can be made 1 day ahead. Store tightly wrapped at room temperature
Sweet Potato-Miso Filling
Preheat oven to 350° F
Peel the sweet potatoes and cut them into smaller pieces. Place them on a lined baking sheet and roast until tender (~ 35 - 40 minutes). Let cool.
Pulse in a food processor until very smooth (you should have ~ 1 cup)
Whisk brown sugar, butter, and miso in a medium bowl until smooth.
Add egg yolks and egg and whisk just enough to incorporate.
Whisk in sweet potato purée, then cream.
Reduce oven temperature to 300° F
Pour the filling into the crust.
Bake pie, rotating halfway through, until the filling is set (it will still wobble slightly in the very center), 50–60 minutes.
Transfer to a wire rack and let the pie cool before slicing about 2 hours.
Serve pie topped with whipped cream or scoops of vanilla ice cream.