Method

• 1.
  Place sugar and 4 cups (1L) cold water in a large saucepan over medium-high heat. Cook, stirring constantly, until sugar dissolves and mixture comes to the boil. Remove pan from heat and cool to room temperature.
• 2.
  Finely grate the zest of the lemons, then halve and juice (you’ll need 1 1/2 cups juice). Discard any lemon seeds. Use a teaspoon to scoop out remaining flesh from inside lemon halves and discard, reserving lemon cups (see recipe notes). Trim bases so lemon cups can stand level, then transfer to a small baking tray, cover and chill until ready to serve.
• 3.
  Stir lemon zest and juice into sugar syrup, then transfer mixture to a deep 4L-capacity airtight freezer-safe container. Cover and freeze for 2 hours, or until edges have started to freeze firm. Remove and use a fork to stir well, mashing mixture as you go to break up the ice. Cover and freeze for 4 hours, or until edges have frozen firm and the centre is almost frozen.
• 4.
  Use a handheld stick blender to blend the mixture in the container, making sure base of blender stays flat on base of container while blending, to prevent aerating the sorbet. Blend until smooth. Cover and freeze sorbet for 4 hours, or overnight, until set.
• 5.
  Spoon scoops of sorbet into lemon cups, top with whipped cream and sprinkle with a few mint leaves. Serve immediately.