Use the sunflower oil to oil a 1.2-litre pudding basin. Tip the dark chocolate, butter and syrup into a heatproof bowl, then put the kettle on to boil. Pour the hot water into a slightly smaller heatproof bowl and sit the bowl of chocolate over it, stirring occasionally until melted.

Meanwhile, put the biscuits in a food bag and use a rolling pin to crush them into smaller pieces. Tip the crushed biscuits, the cranberries and most of the cherries (reserve two for decorating later) into the melted chocolate along with the sea salt flakes. Mix together using a rubber spatula until thick and combined, then scrape into the prepared basin, pushing it down so it’s packed in and comes up the sides. Chill for at least 3 hrs or ideally overnight until the fridge cake is completely set and firm.

Put the kettle on to boil again, then fill a large heatproof bowl with the hot water. Carefully dip the basin into the water until the cake can just be loosened from the sides using a palette or cutlery knife. Invert the cake onto a serving plate and chill to set the sides again. If you like, melt the white chocolate over a bowl of hot water as before, then spoon it over the pudding to create a dripping cream effect. Chill again until set, then decorate with the two reserved cherries and the bay leaves.