Heat the oven to 375F. Spray a 12-cup fluted tube pan with cooking spray. Spoon small dollops of the caramel sauce in a ring in the bottom of the pan.
Place the evaporated milk, cream cheese, 4 of the eggs, vanilla and granulated sugar in blender container. Cover and blend 10 seconds or until smooth. Set aside.
Beat the cake mix, water, oil and remaining 3 eggs in a large bowl on low speed until moistened. Then beat on medium speed until smooth and creamy. Add 1/2 cup of the Daisy Brand Sour Cream to the cake batter; beat until mixed. Spoon and spread the cake batter evenly over the caramel in the pan. Carefully ladle the custard/flan mixture over the cake batter. The pan will be almost full. (The layers will reverse when cooking.)
Place the pan in a larger pan (a roasting pan works well). Add enough hot water to come partway up the outside of the fluted cake pan. Place in the oven. Spray a square of foil with cooking spray; place over the cake pan. Bake for 1 hour to 1 hour 15 minutes or until toothpick comes out clean. Cake may puff up while cooking but will settle back during cooling.
Cool the cake in the pan on a wire rack for 2 hours. Refrigerate for at least 2 hours or until completely cooled. Loosen the cake from the sides of the pan. Invert the cake onto a cake plate. Mix the remaining 1/2 cup Daisy Brand Sour Cream with the powdered sugar. Garnish the top of the cake with the sweetened Daisy Brand Sour Cream.