Heat oven to 350 degrees. Grease the cake pan with butter. Pour 1/4 cup of the caramel topping in bottom of the pan. In large bowl, beat cake mix, water, oil and 3 eggs with electric mixer for about 2 minutes. Pour batter over caramel topping in pan. Place flan ingredients in a blender. Cover and blend on high speed for about 40 seconds. Slowly pour mixture over batter. Bake for about 1 hour or until toothpick inserted in cake comes out clean. Refrigerate for about 4-6 hours and then place serving plate upside down on cake pan; turn plate and pan over. Remove pan. Cut Chocoflan into slices and enjoy!