To make this easy limoncello sorbet, start with either your own batch of homemade limoncello (see below to watch Gennaro Contaldo make his version), or look for a bottle bearing the IGP (Protected Designation of Origin) label and made from Sorrento or Amalfi Coast lemons.
2 cups water
1 & ¼ cups sugar
½ cup fresh lemon juice
½ cup limoncello
zest of 2 lemons
1 pinch of salt
1 carved lemon rind per serving (optional)
Place a ceramic or glass baking dish in the freezer an hour before starting.
Bring the water and sugar just to a boil in a saucepan, stirring frequently, until you have a thick, clear syrup. Remove from heat and let cool. Transfer the syrup to a bowl and add the lemon juice, lemon zest, limoncello, and salt. Combine well and transfer to the baking dish, cover and freeze for at least 3 hours. Check the limoncello sorbet periodically and move it around with a fork.
To make the lemon cups, slice ¾ of an inch off the stem side of the lemons. Using a paring knife and teaspoon, carefully cut and scoop out the lemon pulp. Do this over a bowl so you can save the juice. Slice about ¼ inch from the bottom of the lemons so they will stand up, being careful not to cut so much you make a hole on this side, otherwise the sorbet will leak through the bottom. Freeze the cups along with the sorbet.
When ready, fork the limoncello sorbet to loosen it, then fill the cups (an ice cream scoop works well) and place them back in the freezer until serving. You can make a batch of several sorbet cups in advance.