Make the Cake Batter:
Preheat oven to 350°F (175°C). Grease and flour a 9-inch round or square cake pan.
In a medium bowl, whisk together flour, baking soda, baking powder, salt, and cinnamon. Set aside.
In a large bowl, beat butter, granulated sugar, and brown sugar until light and fluffy.
Add eggs one at a time, mixing well after each. Stir in vanilla extract.
Mix in mashed bananas and buttermilk until combined.
Gradually fold in the dry ingredients, then stir in chopped pecans.
Bake the Cake:
Pour batter into the prepared cake pan and smooth the top.
Bake for 40-45 minutes, or until a toothpick inserted in the center comes out clean.
Let cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
Make the Caramel Sauce:
In a saucepan over medium heat, melt butter and brown sugar.
Add heavy cream and salt, stirring constantly until smooth (about 3-4 minutes).
Remove from heat and stir in vanilla extract. Let cool slightly before using.
Assemble And Serve:
Drizzle warm caramel sauce over the cooled cake.
Sprinkle with extra chopped pecans for garnish.
Slice and enjoy!