Meanwhile, If using a store-bought roll and bake crust, let it come to room temperature. Roll out and fit into a 9 inch pie dish and keep chilled until ready to use.
Preheat oven to 350 degrees F.
Toast the pecans at 350 for about 7 minutes or until fragrant. Set aside to cool, then chop.
Combine the butter and chocolate in a microwave-safe bowl and heat on high, stirring every 30 seconds, until chocolate is melted and mixture is smooth. If you have a microwave-safe mixing bowl, you can do it directly in the mixing bowl. Let the mixture cool for 10 minutes.
Whisk together the chocolate mixture, dark brown sugar, corn syrups, eggs, cocoa powder, bourbon, salt and vanilla.
Sprinkle the toasted nuts over the pie crust, then pour the chocolate mixture over the nuts. They will rise to the top.
Set the pie on a rimmed baking sheet and bake for about 45 minutes.
Allow the pie to cool for several hours. If you want to solidify the chocolate, let cool, then chill, then bring back to room temperature.