Slice the ginger, leaving the skin on, and add to a large pan with 2 litres of water.
Bring to the boil, then reduce the heat to low and leave to simmer for 15 minutes – if you really love ginger and want a super-fiery kick, make it the day before, let the ginger go cold in the water and leave overnight to infuse.
Strain the liquid through a sieve, then squeeze in the lemon juice and add the cloudy apple juice. Bring just to the boil, then add 4 very generous swirls of runny honey and give it a good stir.
To serve, add a shot of rum to a heatproof glass or mug, then top with the hot lemonade. Bottoms up!