Preheat oven to 350°F.
Line a 9x5 loaf pan with parchment.
Brown your butter in a saucepan over medium heat, swirling until golden and nutty.
Cool slightly.
Mix brown butter with both sugars.
Add egg and mix.
Add mashed bananas, Greek yogurt and vanilla bean paste.
In a separate bowl, whisk flour, cinnamon, baking soda, and salt.
Fold into the wet ingredients until just combined.
For the caramel: combine sugar and water in a saucepan over low-medium heat.
Let it simmer without stirring.
Swirl the pan gently to caramelize evenly.
Once golden / amber remove from heat and add the salt and butter carefully (it may sputter) swirl gently until the butter melts and is combined.
Slice or chop the reserved banana and place at the bottom of the loaf pan.
Pour the hot bubbly caramel sauce over the banana.
Pour the batter into the pan over the caramel and banana and smooth it over.
Bake 40-55 minutes or until a toothpick comes out clean.
Once out of the oven flip it over onto a plate or cutting board and remove the parchment paper.
Top with flakey sea salt and enjoy!
