PREHEAT oven to 350 degrees F.
WATERPROOFING STEP 1 (optional but HIGHLY recommended): Place 9” springform pan in the center bottom of a slow cooker liner or oven bag. Bring the liner bag up to the top of the pan then gather excess to one side and tie it in a knot.
WATERPROOFING STEP 2 (do this over liner even if you have already done step 1 for double coverage): Place 2 large 18" x 18" pieces of aluminum foil on a flat surface underneath the pan in the form of a “+.” Gently fold (to make sure you don't create any holes) up the sides of the foil around the (lined) pan.
GREASE: Line bottom of pan with parchment paper and lightly grease the inside of your entire springform pan with nonstick cooking spray.
CRUST: Combine the CRUST ingredients in a medium bowl and stir until well combined. Add to springform pan and firmly press the crumbs down on the bottom of the pan until you have an even layer. (I like to use the bottom of a measuring cup to press down.)
Bake at 350 degrees F for 15 minutes. Remove from oven and cool completely on a wire rack.
TOAST COCONUT AND PECANS: Add coconut to one half of a large jelly roll pan and pecans to the other half. Bake for 12-15 minutes at 350 degrees F (you can bake with your crust), stirring occasionally, until coconut is golden and watching closely towards the end as coconut turns very quickly. Remove from oven and transfer pecans to cutting board. Once cool enough to handle, roughly chop pecans. Set aside.
COCONUT PECAN FILLING: Meanwhile, whisk the egg yolks, evaporated milk and brown sugar together in a large saucepan. Add butter and cook over medium high heat until the sugar dissolves and the butter melts, stirring constantly. Bring to a gentle simmer then turn heat down to medium. Continue to cook, stirring constantly, until thick enough to coat the back of a spoon, approximately 8 minutes. Remove from heat and stir in vanilla, salt, chopped pecans and 1 1/2 cups coconut (save remaining 1/2 cup coconut for topping).
WATER BATH: Fill a roasting pan with 1 1/4 inches water to create a water bath for your cheesecake (to prevent cracking). Place roasting pan in the oven to heat while you prepare your cheesecake filling.
CHEESECAKE FILLING: Add German chocolate and semi-sweet chocolate to a medium bowl and microwave at 50% power at 30 second intervals, until completely melted, stirring after every 30 seconds. Set aside.
Add cream cheese to the bowl of an electric mixer fitted with the paddle attachment and beat on medium speed until light and fluffy, about 4 minutes (no less!). Add sugar and beat 3 additional minutes.
Add cocoa powder and cinnamon and beat until combined. Add the sour cream and vanilla and beat just until blended. Add the eggs, then the egg yolk, 1 at a time, beating as little as possible, just until combined after each addition. Stir in melted chocolate with a spatula just until combined.
ASSEMBLE: Transfer about half of the cheesecake batter to the cooled crust and smooth into an even layer. Spoon about two-thirds of the Coconut Pecan Filling evenly over cheesecake and smooth. Top with remaining cheesecake and smooth. Drop pan on the counter a few times to get rid of any air bubbles. Refrigerate remaining 1/3 Coconut Pecan Filling for later.
BAKE: Add cheesecake to water bath and bake at 350 degrees F for 60-75 minutes OR until edges are firm and the center 2-3 inches of the cheesecake is still wobbly. (DON'T open door before 60 minutes, this can cause cracks.)
COOL: Turn off your oven and crack open the oven door. Allow cheesecake to cool in oven for 60 minutes, then remove to a wire rack and gently run a hot knife along the edges of the cheesecake (to prevent cracking) then continue to cool for 2-3 hours or until cheesecake is completely cooled. Cover the top of the cheesecake with foil, so that it doesn't actually touch the cheesecake. Chill in the refrigerator overnight but best if 24 hours.
GARNISH: Remove cheesecake to serving platter. Stir in 1 tablespoon water to Coconut Pecan Filling (now topping) and microwave approximately 30 seconds, or until softened. Spread over cheesecake and top with reserved coconut. The cheesecake can be refrigerated again at this point or served.
CHOCOLATE DRIZZLE (optional): Just before serving, add chocolate and 1/2 teaspoon shortening to a small microwave safe bowl. Microwave at 30 second intervals, until completely smooth, stirring after every 30 seconds. Add chocolate to a small plastic bag and snip one corner. Drizzle chocolate all over cheesecake.