Makes about 2 ½ cups
2 to 3 large lemons
1 cup filtered or bottled water
½ cup granulated sugar
With a vegetable peeler remove zest in long pieces from 2 lemons. Squeeze 1/2 cup juice from lemons.
In a small heavy saucepan heat water and sugar, stirring until sugar is dissolved. Stir in zest and transfer syrup to a bowl to cool. Chill syrup, covered, until cold. Discard zest and stir in lemon juice.
Freeze lemon mixture in a metal bowl, stirring every 30 minutes to remove ice crystals from side of bowl, until liquid has become granular but is still slightly slushy, about 3 to 4 hours. Serve granita immediately.