Tequila Sunrise slushie

1.For tequila-lime granita, stir sugar and 375ml water in a saucepan over medium-high heat until sugar dissolves, then bring to the boil and cook for 1 minute. Remove from heat, add remaining ingredients, then refrigerate until chilled. Transfer to a container and freeze until firm (overnight). Scrape into ice crystals with a fork and freeze again until required. Scrape with a fork once again just before serving to loosen the ice crystals.

2.To serve, spoon tequila-lime granita into chilled serving glasses and drizzle with crème de cassis. Top up with more granita and serve with extra cassis to taste, and lime wedges.