In a pitcher, combine the limoncello, sparkling water, blueberries, and mint sprigs.
Fill highball glasses halfway with crushed ice. Pour about 1/2 cup of the limoncello mixture over the ice in each glass.
Garnish with mint sprigs and serve.
*Cook's Note: If using frozen blueberries, add them to the pitcher just before serving.
Recipe courtesy of Giada De Laurentiis