Crush the shortbread biscuits and mix with the melted butter in a bowl.
Add to the baking tin and using the back of a spoon press the mixture firmly. Chill in the fridge for 30 minutes.
Meanwhile, add the butter and brown sugar to a saucepan over a low heat and stir until the butter has melted and the sugar has dissolved.
Add ProZero, bring to the boil and simmer for 15 minutes stirring continuously, until the mixture has reduced and thickened.
Take off the heat and leave to cool for 15 minutes.
Pour the caramel onto the biscuit base and chill for a further 10 minutes in the fridge.
Layer on the banana slices and top with the ProZero cream.
Sprinkle with grated Vitabite and chill for 1 hour or until set.
ProZero and Vitabite are foods for special medical purposes and must be used under medical supervision.