Preheat oven to 350 degrees F (about 177 degrees C).
Using a fork, prick bottom of the thawed, plated pie and then line all of the pie crust on top with parchment paper, letting ends extend over edges. Fill with pie weights.
Bake until lightly golden (approximately 15 minutes). Carefully remove pie weights and parchment paper. Let cool completely.
In a large bowl, whisk together pumpkin puree, brown sugar, lightly beaten eggs, melted butter, corn syrup or molasses, flour, vanilla, salt, pumpkin pie spice, and sweetened condensed milk.
Pour mixture into cooled pie crust and cover pie loosely with aluminum foil to prevent excess browning of crust. Bake for 30-40 minutes or just until center is set. Let cool on a wire rack. Meanwhile, make the topping.
To make the Gooey Pecan-Chocolate Topping: In a small saucepan, heat brown sugar, butter, and corn syrup or molasses over medium heat, stirring until sugar dissolves and mixture just starts to boil. Add 1 tablespoon of heavy cream and vanilla, stirring constantly until incorporated.
Stir in the chopped pecans and salt and bring mixture to a boil, stirring constantly. Remove from heat and pour hot gooey pecan topping over the pumpkin pie layer, spreading gently to cover edges of the pumpkin pie. Refrigerate pumpkin pie for at least 8 hours.
Right before serving the best pumpkin pie with gooey pecan topping, melt the chocolate with 4 tablespoons of heavy cream and stir well until combined. Then, drizzle the warm chocolate sauce on top of the pumpkin pie and enjoy!