Preheat the oven to 180ºC (160ºC Fan).
In a large bowl, mash the banana with a fork. Add the sugars and vanilla, mix until fully combined.
Brown the butter in a saucepan, then mix it into the banana mixture along with the egg.
Add the flour, baking powder, and salt, mix until a smooth batter is formed.
Scrape the batter into a parchment-lined pan, spread it into an even layer.
Bake the blondies for 30 minutes or until golden brown, then cool.
Whip the caramel ingredients to make whipped salted caramel.
Spread the whipped caramel over the cooled blondies, top with banana chips and flaked sea salt.
Chill for an hour, then cut into pieces and serve.
