Try another citrus in this recipe, such as fresh lime zest and juice, or even lime- or citrus-flavored vodka. (You may need a little extra sugar, because it isn't naturally as sweet as limoncello liqueur.)
1/2 cup sugar
1 tablespoon lemon zest
3 cups ice cubes
1/2 cup fresh lemon juice
1/2 cup limoncello liqueur (optional)
Garnish: lemon slices
How to Make It
Combine sugar and 1/2 cup water in a small saucepan, and cook over medium heat, stirring often, 3 minutes or until sugar dissolves. Remove pan from heat; stir in lemon zest. Let cool to room temperature, about 30 minutes.
Strain mixture through a fine wire-mesh sieve into a blender, pressing solids with a wooden spoon to extract liquid. Discard solids.
Add ice cubes, lemon juice, and limoncello, if desired, to blender and process until smooth and slushy. Garnish, if desired. Serve immediately.