Preheat oven to 325°F (160°C).
Mix chocolate cookie crumbs with melted butter and press firmly into a springform pan.
Beat cream cheese until smooth, then add sugar and mix until creamy.
Add melted chocolate and vanilla; mix until incorporated.
Add eggs one at a time, mixing slowly. Stir in heavy cream until creamy.
Pour batter over crust.
Bake 55–65 minutes until edges are set and center is slightly wobbly.
Turn off oven, open door slightly, and cool cheesecake inside for 1 hour.
Remove, cool fully, and refrigerate at least 4 hours.
For the topping: Heat evaporated milk, sugar, egg yolks, and butter in a saucepan for 8–10 minutes until thickened.
Remove from heat; stir in coconut, pecans, and vanilla. Cool to room temperature.
Spread coconut-pecan topping over chilled cheesecake before serving.