Preheat the oven: Begin by preheating your oven to 350°F (175°C). Prepare a 9x13 inch baking pan by greasing it well to prevent sticking.
Prepare the cake batter: In a large mixing bowl, combine the box of German chocolate cake mix, 1 1/3 cups of water, 1/2 cup of vegetable oil, and 3 large eggs. Mix on medium speed for about 2 minutes until the batter is smooth and well combined.
Bake the cake: Pour the batter into your prepared baking pan. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Once done, allow the cake to cool for about 10 minutes.
Poke the cake: After cooling, use the handle of a wooden spoon to poke holes evenly across the cake. Ensure the holes are about 1 inch apart. This allows the filling to seep in.
Add the filling: In a bowl, mix together the 1 can of sweetened condensed milk and 1 jar of caramel topping. Pour this mixture over the cake, ensuring it fills all the holes and coats the surface.
Prepare the topping: In a medium saucepan, combine 1 can of evaporated milk, 1/2 cup of granulated sugar, 1/2 cup of light brown sugar, 1/2 cup of unsalted butter, and the 3 large lightly beaten egg yolks. Cook over medium heat, stirring continuously. Allow the mixture to thicken for 10-12 minutes.
Add flavors and elements: Once thickened, remove from heat. Stir in 1 tsp of vanilla extract, 1 cup of chopped pecans, and 1 cup of sweetened shredded coconut until well mixed.
Top the cake: Evenly spread this coconut-pecan topping over the cake while it is still warm. The heat will help it adhere beautifully.
Add the chocolate chips: Sprinkle 1 1/2 cups of semi-sweet chocolate chips over the warm topping. Let them sit for a few minutes to melt, then spread them evenly across the cake for a luscious finish.
Cool and serve: Allow the cake to cool completely before cutting into it. This ensures the layers set well and enhances the flavor.