*Can be found at specialty Latin markets
In a medium saucepan, combine the water, hibiscus flowers, and sugar over medium-high heat. Bring the mixture to a boil, stirring occasionally, until the sugar has dissolved. Allow the mixture to cool for 25 minutes. Add the lemon juice, lime juice, and vodka.
Place the ice in a tall pitcher. Strain the hibiscus tea into the pitcher and discard the flowers. Refrigerate until ready to use.
Recipe courtesy of Giada De Laurentiis, 2008