Melt 75g of the chocolate in the microwave in 30 second bursts. Whizz the biscuits in a food processor into crumbs. Pour the melted chocolate onto the biscuit crumbs and whizz again. Spread the biscuit mixture across the base and up the sides of a 16-18cm shallow pie or cake tin, then put in the fridge to set

Sprinkle the butterscotch pudding powder into the milk and whisk together until smooth. Slice the bananas. Take the tin out of the fridge and spread the salted caramel sauce over the base. Cover the caramel with the banana slices. The pudding will have started to thicken, so give it a brief whisk, then spoon it over the bananas. Put in the fridge for 5-10 mins to set. Melt the remaining chocolate and drizzle over the pie to serve.