Preheat oven to 190 degrees C and line the bottom of a baking tray with baking paper.
Cut 1 pastry sheet into 8 even pieces and place on the baking tray.
Cover pastry with a piece of baking paper and place another baking tray on top, so it doesn't rise. Cook for 15 mins or until nicely brown. Repeat with the remaining pastry and let cool.
Spread 8 pieces of pastry with the jam, 8 pieces with the lemon butter and 8 pieces with the Nutella. Place slices of banana on top of the Nutella.
Place a couple of heaped dessertspoons of cream on top of each filling.
Cover fillings with the rest of the pastry pieces. Dust with the icing sugar.