Lemon sorbet

1 . Stage

Heat 250ml water, the sugar and the lemon peel in a small pan until the sugar has dissolved then bring the mixture to the boil. Cook for 3 mins then turn off the heat and leave to cool. Pick out the lemon peel and discard. Measure out 100ml of lemon juice and add to the sugar mixture along with the vodka if using.

2 . Stage

Pour into a freezer box and freeze for 1hr 30 mins then mix up with a whisk to break up and incorporate the ice crystals (which will be starting to form at the edges) before returning to the freezer.

3 . Stage

Keep mixing the sorbet once an hour for 4 hours to break up the ice crystals. Stop mixing when firm but still scoopable then store in the freezer for up to 1 month. Serve scoops of sorbet decorated with a few curls of lemon zest.