1) Stir first 5 ingredients together in a small pan until everything is evenly distributed. Cook on medium heat for about 15 minutes or until everything is pretty well broken down, stirring occasionally. You can mash any large pieces up with a potato masher if you like a smoother syrup.
2) Remove from heat. Taste for sweetness and add agave if it seems a little too tart. Let stand for about 10 minutes before serving. Enjoy!
Source of recipe: I had about 2 pounds of free rhubarb and didn't know what to do with it. So I altered the whole fruit syrup recipe from Vegan Brunch to make this. It turned out pretty darn good. I served my first batch in crepes, but am excited to try this on pancakes.