Step 1 If you have an espresso machine, make 2 1/2 cups of extra-strong espresso. If not, put the water in a saucepan, add the coffee grounds, bring to a boil and immediately turn off the heat.
Step 2 Add the lemon zest to the coffee and allow it to infuse for 5 minutes. Strain (through a coffee filter, if you aren't using an espresso machine). Mix in the sugar while the coffee is still warm. Stir in the lemon juice.
Step 3Freeze the mixture and follow the four-time scraping and freezing process described in the star anise and grapefruit granita recipe. Serve with whipped cream, if desired.