1. Preheat and Prepare Pans:
Preheat your oven to 350°F (175°C). Grease and flour three 9-inch round cake pans.

2. Mix Dry Ingredients:
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

3. Cream Butter and Sugars:
In a large mixing bowl, beat the softened butter, granulated sugar, and brown sugar until light and fluffy. This step helps create a tender cake texture.

4. Add Eggs and Flavor:
Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract and mashed bananas. Mix until smooth.

5. Combine Wet and Dry Ingredients:
Gradually add the dry ingredients to the banana mixture, alternating with buttermilk. Begin and end with the dry ingredients. Gently fold in the chopped pecans.

6. Bake the Cake Layers:
Divide the batter evenly among the prepared cake pans. Smooth the tops with a spatula. Bake for 25–30 minutes, or until a toothpick inserted into the center of the cakes comes out clean. Let the cakes cool in their pans for 10 minutes before transferring them to a wire rack to cool completely.

7. Make the Caramel Frosting:
In a medium saucepan, melt the butter over medium heat. Add the brown sugar and heavy cream, stirring constantly until the mixture comes to a boil. Remove from heat and let cool slightly. Gradually beat in the powdered sugar and vanilla extract until the frosting is smooth and creamy. Adjust the consistency by adding more cream if needed.

8. Assemble the Cake:
Place one cake layer on a serving plate. Spread a generous layer of caramel frosting over the top. Repeat with the second and third layers, then frost the sides of the cake. Garnish the top with chopped pecans for a beautiful finish.

9. Set and Serve:
Allow the frosting to set for about 15 minutes at room temperature. Slice and serve this decadent treat!