- 20g dried hibiscus
- 5tbsp caster sugar
- 650g watermelon flesh, seeds removed and roughly chopped
- Juice of 3 limes, plus lime slices to serve
- Ice, to serve
- 4 sprigs of fresh mint to serve (optional)
- In a jug infuse the hibiscus with 200ml just-boiled water and leave to infuse for 15 minutes.
- Strain into a small saucepan and discard the hibiscus flowers.
- Mix with the sugar, heat gently until dissolved then turn the heat to medium and simmer for 5-8 minutes, until syrupy. Leave to cool.
- Blitz the watermelon in a liquidiser until smooth then transfer to a large measuring jug, mix with the hibiscus syrup and lime juice and add water to make it up to 1 litre. Taste and add more sugar if you like.
- Chill until cold then divide between 4 glasses and serve with ice and lime wedges. Garnish each glass with a sprig of fresh mint, if you like.