Gin and tonic granite

The perfect summer treat – ice-cold, refreshing and mind-numbingly good (quite literally, if you eat too much of it). Makes around a litre.

Ingredients

100ml water
200g caster or granulated sugar
250ml good gin (Bombay Sapphire or Beefeater)
Juice of 2 lemons
500ml tonic water

Heat the water with the sugar until the latter dissolves. Add all the remaining ingredients to the pan, stir, then pour into a freezer container and freeze. After an hour, take it out, give it a quick whisk and return to the freezer. Repeat after the second hour.

Before serving, scrape the granite all over with a fork to break it up – this will give it a softer texture. Serve as a pre-dessert (a few crystallised violet petals scattered on top are a nice touch) or as a grown-up's slushy for a hot day.