Preheat oven to 350 degrees F. Spray a 12 cup Bundt pan with flour-added cooking spray or grease the pan with shortening and dust with flour. Stuff some aluminum foil in the center hole. Pour caramel topping into the pan.
Prepare cake mix according to package directions. Pour the cake batter into the cake pan over the caramel topping.
Make the flan. Pour condensed, evaporated and fresh milk into a blender. Add softened cream cheese, vanilla, eggs, and blend or process till smooth. (Side note, do not think that fill capacity line on a food processor is joking, they are dangerous, or you will end up with an overflowing mess. Just saying.) Pour the flan mixture very slowly over the cake batter.
Spray with a large sheet of aluminum foil with cooking spray. Cover the cake with the aluminum and seal tightly. Place covered bundt pan inside a roasting pan like depicted. Add about a two-inch depth of hot kettle water to the roaster. This will be a water bath that makes that flan cook evenly. Place in middle rack of the oven and set your timer for two hours.
After two hours, remove cake from water and allow to cool for 15 minutes on a wire rack. Then remove the foil cover. Cool one hour then invert cake onto a larger plate with rim. The caramel topping should ooze down the sides. Cool completely, then refrigerate.
Recipe by midwestandgrassfed.com at https://www.midwestandgrassfed.com/magical-flan-cake-resurrected/