Preparation Bring 8 cups water to boil in large pot. Add piloncillo and flowers. Return water to boil, stirring to dissolve piloncillo. Reduce heat and simmer uncovered 10 minutes to blend flavors. Strain liquid into pitcher. Chill until cold. (Can be made 1 day ahead. Cover and keep chilled.) Fill glasses with ice and citrus slices. Pour liquid over and serve immediately.
Preparation Bring 8 cups water to boil in large pot. Add piloncillo and flowers. Return water to boil, stirring to dissolve piloncillo. Reduce heat and simmer uncovered 10 minutes to blend flavors. Strain liquid into pitcher. Chill until cold. (Can be made 1 day ahead. Cover and keep chilled.) Fill glasses with ice and citrus slices. Pour liquid over and serve immediately.