Prepare the Cake Batter
Preheat oven to 350°F (175°C). Grease and flour a 9-inch round or loaf cake pan.
In a bowl, whisk flour, baking soda, baking powder, salt, and cinnamon.
In a separate large bowl, cream together butter and brown sugar until light and fluffy.
Add eggs, one at a time, beating well. Stir in mashed bananas, sour cream, and vanilla extract.
Gradually mix in the dry ingredients until just combined. Fold in chopped pecans.
Bake the Cake
Pour batter into the prepared pan and bake for 35-40 minutes, or until a toothpick inserted comes out clean.
Let the cake cool in the pan for 10 minutes, then transfer to a wire rack.
Make the Caramel Glaze
In a saucepan over medium heat, melt butter and brown sugar. Stir constantly for 2-3 minutes.
Add heavy cream, vanilla, and salt, stirring until smooth and slightly thickened. Remove from heat.
Assemble And Serve
Pour the warm caramel glaze over the cake, letting it drip down the sides.
Sprinkle with additional pecans, if desired.
Let set for 10 minutes, then slice and enjoy!