blue martinis

INGREDIENTS
1 cup sugar
4 tsp. crushed red pepper flakes
1/4 tsp. kosher salt
2 3′ pieces fresh ginger, peeled and finely chopped
12 lime wedges
6 cups soda water, divided

Combine sugar, red pepper flakes, salt, ginger, and 2 cups water in a small saucepan. Bring to a boil, reduce heat to low, and simmer for 15 minutes. Remove pan from heat, cover, and steep for 30 minutes. Strain ginger syrup into a jar and chill. Fill a 12-oz. glass with ice cubes. Add 2 Tbsp. ginger syrup, squeeze a lime wedge into glass, and top with soda water. Stir to combine. Repeat to make 11 more sodas.

http://www.bonappetit.com/recipe/spicy-ginger-soda