Generously grease a 1.5 pint pudding basin with a little butter. Cut out a small disc of parchment paper an lay it on the bottom of the basin

Spoon the mixture into the pudding basin, pressing the contents down firmly with the back of the spoon

Lay a circle of parchment paper over the top of the filled pudding bowl so that there’s a 2cm overhang

Cover the parchment paper with a pleated layer of tin foil, also with a 2cm overhang

Secure the parchment/tin foil overhang with string tied around the circumference of the pudding bowl, under the lip

Attach another piece of string to act as a lifting handle

Simmer the pudding in a steamer (or lidded saucepan with a trivet/upturned saucer and hot water that reaches halfway up the sides of the bowl) for 5 hours topping up the water level when necessary

When cooked, allow to cool completely, remove the parchment & tin foil cover and string and replace with new. Store in a cool dry place, ready for reheating on Christmas day. Reheating will take about 90 minutes, steaming using the same method

Once reheated, invert on to a serving plate and remove the disc of parchment paper. Just before serving, pour over a couple of tablespoons of rum that has been warmed in a little saucepan. Carefully set it alight