Ingredients:
1/3 cup granulated sugar
1/2 cup water
1/2 cup packed fresh mint leaves, plus sprigs for garnish
1 ruby-red grapefruit
3/4 cup white rum
3 cups ice
1 cup seltzer

Directions:
Bring sugar and water to a boil in a small saucepan.
Remove from heat, and add mint leaves. Let steep 10 minutes.
Strain through a fine sieve into a small bowl, and discard mint. Let cool.
Using a vegetable peeler, remove zest from grapefruit in long, wide strips.
Place in a large glass, and add rum.
Cover, and let stand for 30 minutes.
Strain through a fine sieve into a large glass measure, and discard zest.
Cut away remaining pith from grapefruit.
Cut between membranes to release segments.
For each drink, place 2 to 3 segments in a glass.
Top with 3/4 cup ice.
Stir 3 tablespoons infused rum, 2 tablespoons mint syrup, and 1/4 cup seltzer in a glass measure, and pour over ice. Garnish with mint sprigs.