Combine rhubarb, sugar, and water in a medium pot over high heat, stirring constantly until sugar dissolves.
Bring mixture to a boil, then reduce heat to a simmer. Cook until rhubarb is soft and starting to fall apart, stirring frequently (about 5 to 7 minutes).
Remove from heat, then let cool for about 10 minutes.
Place a fine mesh strainer over a large bowl, then transfer rhubarb mixture to strainer.
Stir rhubarb mixture until most liquid has drained into bowl, then firmly press the pulp with the back of a spoon to extract the remaining liquid.
Chill syrup before using.
Prepare Soda:
Place ⅓ cup chilled syrup in the bottom of a glass.
Top syrup with ⅔ cup sparkling water. Stir well.
Fill glass with ice, then serve. Enjoy!
Notes
Customize the flavor and sweetness by adjusting the proportions of syrup to sparkling water. Here are some suggestions:
½ cup syrup + ½ cup sparkling water (most sweet)
⅓ cup syrup + ⅔ cup sparkling water (this is my fave, and what I recommend above)
¼ cup syrup + ¾ cup sparkling water (least sweet)
You will have leftover syrup. Feel free to cut the recipe in half, or use it to make other drinks (like this tasty Rhubarb Lemonade), or make more soft drinks!If you have a food scale, use it to weigh the rhubarb. You'll get a more accurate measure of the amount than you would with cups. This is the scale that I use (and recommend).Save the rhubarb pulp that's leftover when making the syrup. It makes a tasty "jam" that's great on bagels, toast, and more!Check out the info before this recipe card for more tips, variations, and related recipes!