Preheat your oven to 350°F (175°C). In a large mixing bowl, cream together 1 cup of unsalted butter and 1 cup of granulated sugar until light and fluffy, about 3-5 minutes. Add in 3 large eggs one at a time, mixing well after each. Gradually mix in 2 cups of cake flour, 2 teaspoons of baking powder, 0.5 teaspoon of salt, and 0.5 cup of milk until the batter is smooth.

Divide the prepared batter between two greased 9-inch cake pans. Smooth the tops and bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean. Cool in the pans for 10 minutes before transferring to wire racks to cool completely.

In a medium mixing bowl, combine 1 cup of softened unsalted butter and 1 cup of caramel sauce. Whip on medium speed until light and fluffy, about 3-4 minutes.

Once the cakes are cooled, place one layer on a serving plate and spread a generous layer of caramel frosting on top. Place the second layer on top and frost the top and sides with the remaining frosting.

Sprinkle a generous amount of caramel crunch over the frosted cake. Optionally, drizzle additional caramel sauce for extra sweetness.

Chill the assembled cake in the refrigerator for at least 30 minutes before slicing and serving.