Preheat your oven to 350°F (175°C) and grease and flour three 9-inch round cake pans.

In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Beat in the eggs one at a time, ensuring they are fully incorporated before adding the next. Then stir in the vanilla extract.

In another bowl, whisk together the flour, baking powder, baking soda, and salt.

Alternately add the dry ingredients and buttermilk to the wet mixture, starting and ending with the dry ingredients.

Divide the batter evenly among the prepared cake pans. Bake in the preheated oven for 25-30 minutes or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for about 10 minutes, then transfer them to wire racks to cool completely.

In a saucepan over medium heat, combine brown sugar, heavy cream, and butter. Stir continuously until the mixture begins to boil.

Let it simmer for about 5 minutes until it thickens. Remove from heat, then stir in the vanilla extract and chopped pecans.

Once the cakes are completely cool, place one layer on a serving platter and spread a generous amount of caramel sauce on top.

Repeat this for the second layer and finally top with the third layer. Drizzle the remaining caramel sauce over the top.