Ingredients
1 (3-inch long) piece fresh ginger, peeled and thinly sliced (about 1/3 cup)
1/4 cup sugar
1/4 cup honey
4 cups freshly squeezed ruby-red grapefruit juice (about 5 grapefruits)
Ice cubes, for serving
1 can (12-ounce) club soda
Preparation
In a small saucepan, combine ginger, sugar, honey, and 1/4 cup water over medium heat, stirring until sugar is dissolved, about 2 minutes.
Place grapefruit juice in a pitcher. Strain ginger syrup through a fine-mesh sieve into pitcher. To serve, divide juice mixture among 6 glasses filled with ice, and top off with a splash of club soda.