To make the cake, preheat the oven to 350 degrees F.
In a large bowl, combine the melted butter, brown sugar, vanilla extract, shredded apples, and eggs.
Fold in the all-purpose flour, cinnamon, baking powder, baking soda, and salt.
Distribute the batter evenly amongst 3 buttered 8-inch cake pans.
Bake for 27 minutes or until done.
Let the cakes cool completely.
To make the cream cheese frosting, mix the unsalted butter and cream cheese using an electric whisk for 2-3 minutes.
Stir in the vanilla extract and whole milk and mix on high for 2 minutes or until nice and fluffy.
To make the salted caramel, cook the sugar in a medium saucepan over medium heat, stirring constantly, until the sugar dissolves completely and turns into a copper color.
Stir in the butter using a whisk until it melts completely.
Stir in the heavy cream slowly while whisking.
Cook for an additional minute.
Stir in the salt.