Step 1

Put the Oreos and cocoa powder into a food processor and whizz until the mixture resembles dark breadcrumbs. Pour in the melted butter and whizz briefly to combine, then press the crumbs into the prepared tin to form a flat base. Chill in the fridge for 30 minutes.

Step 2

Soak the gelatine leaves in a small bowl of cold water. Put the rest of the filling ingredients in a large mixing bowl and beat with an electric mixer for 4-5 minutes until the mixture has stiffened and started to lose its shine. Put 5 tbsp of the mixture into a small saucepan and heat gently until warm, then squeeze out the gelatine leaves and add to the saucepan, stirring until melted. Pour the gelatine mixture into the bowl containing the filling ingredients and whisk for 2 minutes. Pour the filling onto the Oreo crust inside the tin, then shake gently to level out. Leave the cheesecake to set in the fridge overnight.

Step 3

To make the topping, heat 50g of the butter, the sugar and cinnamon in a frying pan over a medium-high heat. When the butter has melted, mix well and turn up the heat slightly. Cook for about 3 minutes until the mixture starts to turn dark brown, then take the pan off the heat and stir in the rum (if using) – be careful, it might spit.

Step 4

Melt the remaining 20g butter in a small frying pan over a medium heat. Turn up the heat to high and fry the bananas for a few minutes on each side until golden.

Step 5

Remove the cheesecake from the tin (you may need to warm the outside of the tin with your hands for a few minutes first), then top with the bananas and pour over the caramel sauce. Serve immediately.