Preheat the oven to 350 degrees F. Butter and flour a 10-inch Bundt pan.
In a large bowl, cream the butter and brown sugar until light and fluffy.
Add the eggs one at a time, beating well after each addition, then beat in the vanilla.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
With the mixer on low, add the dry ingredients to the wet in three additions, alternating with the caramel sauce, and end with the dry ingredients.
Pour the batter into the prepared Bundt pan and bake for 50-60 minutes, until a toothpick inserted in the center comes out clean.
Let the cake cool in the pan for 15 minutes, then invert onto a wire rack to cool completely.
If desired, drizzle extra caramel sauce over the cooled cake for topping.
Notes
Tip: This cake keeps well for several days stored in an airtight container at room temperature. For extra richness, serve with a scoop of vanilla ice cream.