Preheat oven to 325°F (160°C). Mix crushed cookies and melted butter. Press firmly into the bottom of a 9-inch springform pan. Bake for 10 minutes. Let cool.

In a large bowl, beat cream cheese until smooth. Add sugar and melted chocolate; beat to combine. Add eggs one at a time, mixing well after each. Stir in vanilla and sour cream.

Pour filling over cooled crust. Bake for 50–55 minutes, until center is just set. Turn off oven, crack the door, and let the cheesecake rest for 1 hour. Chill in the fridge for at least 4 hours or overnight.

In a medium saucepan, whisk evaporated milk, brown sugar, egg yolks, and butter over medium heat. Stir constantly until thickened (about 10–12 minutes). Remove from heat and stir in vanilla, coconut, and pecans. Cool completely.

Spread cooled topping over the chilled cheesecake. Keep refrigerated until ready to serve.