Pour the caramel sauce into the bottom of a Bundt pan and set aside.
Place the sweetened condensed milk, cream cheese, milk, vanilla, and 2 eggs into a blender and blend until smooth. Set aside.
In a large bowl add the chocolate cake mix, 3 eggs, oil, water, sour cream and mix. Pour the chocolate batter over the caramel sauce in the pan.
Top the chocolate batter with the flan liquid. Cover the Bundt pan with foil.
Place the Bundt pan into a larger roasting pan and fill the larger pan with enough water to come half-way up the Bundt pan.
Bake for 1 hour to 1 hour 15 minutes or until a toothpick into the cake section comes out clean. Once cooled (about 2 hours), invert the cake onto a platter. Garnish as desired and serve.