Prepare the potatoes for baking by preheating your oven to 400 degrees F and greasing a baking sheet with vegetable oil. Peel the sweet potatoes and cut into 1/4-inch slices before placing them on the prepared baking sheet. Use your hands to rub each slice with oil, then transfer to the oven and bake for 25 minutes or until golden brown. Allow to cool before use.

Make the pie crust by combining both pie crusts in a medium-sized bowl and rolling them out on a lightly floured surface. Use a rolling pin until the dough is around ⅛ of an inch thick. Place the dough into a 9-inch round or rectangular dish and trim off any excess dough. Bake in preheated oven for eight minutes or until golden brown. Allow to cool before using.

Prepare the custard filling by creaming together butter, white sugar, and brown sugar in a medium bowl until light and fluffy. Add eggs one at a time, then add the cacao powder, cinnamon, clove, and flour. Slowly add the heavy cream and vanilla extract and mix until fully incorporated.

Assemble the pie by layering half of the sweet potato slices into the prepared crust first, then pour in the custard and spread it evenly. Top with remaining sweet potatoes and lightly press down.

Bake and serve by transferring to a preheated oven for 40 minutes or until golden brown on top. Allow to cool and serve with a dollop of whipped topping for added sweetness, if desired.