Rhubarb-Vanilla Soda

 

2 pounds rhubarb, roughly chopped

1 cup sugar

1 whole vanilla bean

Sparkling water

 

Combine the rhubarb and the sugar in a medium saucepan. Split the vanilla bean down its length, scrape out the seeds, and add both the seeds and the pod to the pan. Stir in 2 cups of tap water. Bring to a boil over medium heat, then lower to a simmer and cook until the rhubarb has completely broken down into a thick, jam-like mash, about 15 minutes. Remove the pan from the heat and let the rhubarb cool until it is no longer steaming. Strain through a fine-mesh strainer, pressing down on the fruit to extract as much juice as possible. (You should have between 3 and 4 cups of syrup.) Let the syrup cool completely. Store the cooled syrup in a sealed container in the refrigerator. The syrup will keep refrigerated for about 2 weeks. To serve, combine ⅓ to ½ cup of chilled syrup with 1 cup of sparkling water.