Preheat oven to 325°F (165°C). Grease and flour a 10-inch bundt pan.
In a large bowl, cream together butter and sugar until light and fluffy. Add eggs one at a time, mixing well after each addition. Stir in vanilla.
In another bowl, whisk together flour, baking powder, baking soda, and salt. Gradually add to the creamed mixture alternately with buttermilk, beginning and ending with flour mixture. Mix until just combined.
Pour half of the batter into the prepared pan. Drizzle with half of the caramel sauce. Top with remaining batter.
Bake for 60-70 minutes or until a toothpick inserted into the center comes out clean. Cool in pan for 10 minutes, then invert onto a wire rack to cool completely.
Drizzle with additional caramel sauce before serving.
