Whisk together the flour, brown sugar, baking powder, baking soda, cinnamon, and salt in a large bowl.
Mash the ripe banana until smooth, then whisk it with the buttermilk, melted butter, and vanilla. Stir into the dry ingredients just until combined and rest 5 minutes.
Cook 1/4 cup portions on a greased griddle over medium heat until bubbles form, then flip and cook until golden on both sides.
For the topping, melt the butter with the brown sugar in a skillet over medium heat and let it bubble for 2 minutes, stirring often.
Stir in the heavy cream and cinnamon and simmer 1 minute until you have a glossy caramel.
Add the banana slices and gently toss to coat, cooking 1 to 2 minutes until just softened. Take off the heat and stir in the vanilla and pecans.
Spoon the warm caramel bananas over the pancake stacks and serve immediately for a true dessert for breakfast moment.
