Prepare a sponge cake according to recipe instructions. Once cooled, slice the cake into three even layers.
Apple Filling
Peel and slice each apple into about 10 evenly sized pieces.
In a skillet over medium heat, cook the apples alongside the apple juice, brown sugar, and a tablespoon of butter. Keep stirring the mixture periodically until all the sugar dissolves and turns into a syrup.
Excluding the very top layer, spread the apple mixture over the top of the other two cake layers. Set the layers aside to give the juice time to absorb and soak in.
Caramel Cake Cream
Using an electric mixer, beat the softened butter, softened cream cheese, and dulce de leche together until smooth. Next, add the heavy whipping cream and beat until you get stiff peaks. Be extra careful not to overmix the cream once you add the whipping cream, as it will turn into butter.
Apply a generous amount of cream to the bottom cake layer (on top of the apples) and cover it with the second cake layer. Apply cream to the second layer. Finally, place the top layer on. Frost the outside of the cake with the remaining cake cream.
Decorate the cake as you wish. Fresh apples and chopped walnuts work great. Refrigerate the cake overnight to allow the juice to soak in even more. Slice and enjoy!