'2 large stalks celery, coarsely chopped', '1 teaspoon celery seeds', '1/4 teaspoon coriander seeds', '1 cup seedless green grapes', '1 cup still water', '4 cups sparkling water'
1. Puree the chopped celery, celery seeds, coriander seeds, and grapes in a blender with the still water. Strain through a fine-mesh sieve into a large pitcher.
2. Add the sparkling water, stir gently, and serve.