1. Prepare the cake batter:

• Preheat your oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan or two 9-inch round pans.
• In a medium bowl, whisk together the flour, baking soda, baking powder, salt, and cinnamon (if using).
• In a large bowl, cream the butter, granulated sugar, and brown sugar together until light and fluffy.
• Beat in the eggs one at a time, then add the vanilla extract.
• Mix in the mashed bananas until combined.
• Gradually add the dry ingredients to the wet ingredients, alternating with the buttermilk, starting and ending with the dry ingredients.
• Fold in the chopped pecans.

2. Bake the cake:

• Pour the batter into the prepared pan(s) and spread evenly.
• Bake for 35–40 minutes (for a 9×13 pan) or 30–35 minutes (for round pans), 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.

3. Prepare the caramel glaze:

• In a small saucepan, melt the butter and brown sugar over medium heat, stirring until the sugar dissolves.
• Add the heavy cream, vanilla extract, and salt. Stir and bring to a gentle boil. Cook for 1–2 minutes, then remove from heat. Let cool slightly.

4. Assemble the cake:

• Pour the warm caramel glaze over the cooled cake, spreading evenly. If using round pans, you can pour some glaze between the layers as well.
• Sprinkle additional chopped pecans on top for garnish, if desired.

5. Serve:

• Let the glaze set for 10–15 minutes before slicing. Serve warm or at room temperature.