Prepare the Coconut-Pecan Topping : In a medium saucepan, whisk together the egg yolks, evaporated milk, and vanilla extract. Add the sugar and cubed butter. Cook over medium heat, stirring constantly, until the mixture thickens (about 10 minutes). Remove from heat and stir in the shredded coconut and toasted pecans. Allow the topping to cool completely before using.

Make the Oreo Crust : Preheat the oven to 325°F (163°C). In a medium bowl, mix the Oreo crumbs and melted butter until evenly combined. Press the mixture into the bottom of a 9-inch springform pan, creating an even layer. Bake for 8-10 minutes, then set aside to cool.

Prepare the Cheesecake Filling : In a large mixing bowl, beat the cream cheese and sugar on medium speed until smooth and creamy. Add the flour and cocoa powder, mixing until well combined. Mix in the sour cream and vanilla extract, followed by the melted German chocolate. Add the eggs one at a time, mixing on low speed after each addition. Be careful not to overmix to prevent air bubbles.

Assemble and Bake the Cheesecake : Pour the cheesecake filling over the cooled Oreo crust in the springform pan. Place the pan in a water bath by setting it in a larger baking dish and filling the dish with 1 inch of hot water. This prevents cracks in the cheesecake. Bake at 325°F (163°C) for 75-85 minutes, or until the edges are set and the center has a slight jiggle. Turn off the oven, crack the door slightly, and let the cheesecake cool inside for 1 hour. Remove the cheesecake from the water bath and allow it to cool to room temperature. Refrigerate for at least 4 hours, preferably overnight.

Add the Coconut-Pecan Topping : Once the cheesecake is fully chilled, spread the coconut-pecan topping evenly over the top. Optional: Drizzle with chocolate ganache or sauce for an extra decadent touch.

Serve and Enjoy : Slice the cheesecake with a sharp knife, wiping the blade clean between cuts for neat slices. Serve chilled and enjoy the layers of chocolatey, nutty, and creamy goodness!