Sweet Potato Filling:Combine mashed sweet potatoes, sugars, egg, cream, vanilla, salt, cinnamon, allspice, nutmeg and butter in an electric mixing bowl and beat at medium-low speed until smooth (do not overmix).
Pecan Filling: Combine all ingredients.
Bourbon sauce: Whisk all ingredients together until creamy and smooth.
To Assemble: Spoon sweet potato filling into the pastry shell.
Fill shell evenly to the top with the pecan filling.
Bake at 1 1/2 hours or until a knife inserted into the center of the pie comes out clean.
Store pie at room temperature for 24 hours before serving.