Muffins: Preheat oven to 180 degrees C. Line a muffin tray with patty cases.
Mix the chestnut flour, baking powder and sugar together in a large bowl. Mix the butter, vanilla essence and eggs together in another bowl.
Pour the liquid mixture into dry mixture. Stir the batter just enough to mix together. The muffin batter should not be mixed for too long.
Fill the patty cups with the batter; no more than 2/3 of the way. Bake for about 20 minutes keeping an eye on them while they cook. Once cooked, remove from the oven and cool before adding the topping.
Bananas: Cut the bananas into thick slices and add them to a frying pan over high heat. Sprinkle with sugar and turn the slices over until golden brown, sprinkle them again with sugar and turn them over. Remove from the heat and cool.
Icing: In a bowl mix the cream cheese and soft butter with a fork. Add the vanilla essence and icing sugar to the bowl and mix.
To Serve: Using a melon baller cut into the top of the muffin. Add a slice of caramelised banana and then cover with icing using a pastry bag. Top with a banana slice.