Preheat your oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.
Add the mashed bananas, eggs, bourbon, and vanilla extract to the butter mixture. Mix until well combined.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the banana mixture, alternating with the buttermilk. Mix until just combined.
Pour the batter into the prepared baking pan and smooth the top. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
While the cake is cooling, prepare the caramel frosting. In a saucepan over medium heat, melt the butter. Stir in the brown sugar and heavy cream, bringing the mixture to a boil. Boil for 2 minutes, stirring constantly. Remove from heat and stir in the vanilla extract.
Gradually whisk in the powdered sugar until smooth and creamy. Allow the frosting to cool slightly before spreading it over the cooled cake.
Slice and serve the cake. Enjoy!