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

Beat the softened butter and granulated sugar until light and fluffy. Add the eggs one at a time, mixing well after each addition.

Whisk together the flour, baking powder, baking soda, and salt in another bowl. Gradually add the dry mixture to the wet ingredients, stirring until just combined.

Pour the batter evenly into the prepared pans and bake for about 25-30 minutes or until a toothpick inserted in the center comes out clean.

In a saucepan, combine brown sugar, heavy cream, and butter over medium heat. Stir until everything is melted, then bring to a gentle simmer for about 5-7 minutes until it thickens slightly. Remove from heat and stir in the vanilla.

Once the cakes are completely cool, layer them on a cake stand. Drizzle warm caramel sauce between the layers, add chopped pecans, and top with remaining caramel and a sprinkle of sea salt.