1 Remove four thin slices from the cucumber and thread them onto toothpicks. Dice the remaining cucumber.
2 Combine the diced cucumber with the rocket, lemon juice, yoghurt, and sugar in a food processor or blender.
3 Blend on high for 2 minutes. Scrape down the sides, stir well, and add the crushed ice.
4 Blend again for a further minute.
5 Pour into glasses and serve with a garnish of the cucumber slices on toothpicks.