Preheat the oven to 350. Add the butter to a large pan over medium heat. Let the butter melt and continue to cook until it foams up. Let it cook for 4-5 minutes until the foam subsides and you’re left with brown, nutty smelling butter.
Take the pan off the heat and add the brown sugar and stir until combined. When the butter has cooled down for at least 5 minutes, add the eggs, one at a time, stirring thoroughly and quickly between each addition. Then add the vanilla and stir again.
Mash the bananas in a bowl then add them to the mixture and combine. Sift in the dry ingredients and mix until just combined. Pour into a lined or greased 9x9 pan. Bake for 45-55 minutes, until the middle is just set.
While the blondies are cooling, make the frosting. In a bowl, combine the instant pudding mix, powdered sugar, milk, and vanilla. Whisk until smooth and put in the fridge. Pour the heavy cream into a bowl and whisk until stiff peaks form. Take the pudding mixture out of the fridge and fold in the whipped cream.
When the blondies are cooled, pipe on the pudding frosting and top with a slice of banana and a vanilla wafer. Enjoy!