Cucumber & lime granita

Put the cucumber in a blender with 6 tbsp agave, the lime zest and juice, mint leaves and salt. Add ­150ml water and whizz until smooth. Taste and add more agave, if needed. Pour into a large tray or airtight container, then freeze for around 8 hours, using a fork to mix and scrape up the increasingly solid juice every ­1-2 hours, until full of fluffy ice crystals.

When the granita is ready, give it one more scrape with a fork, then spoon into serving glasses. Add a shot of tequila for a refreshing cocktail, if liked.