Chop the rhubarb into 1/2 inch pieces and add to a medium-sized cooking pot.
Add the sugar to the bowl and mix well making sure all the rhubarb is coated. Cover with plastic and let the mixture macerate in the fridge overnight.
The next morning heat the mixture over medium heat until it starts to come to a boil. Turn the heat down and simmer for about 10 minutes or until the mixture has thickened to a jam-like consistency and the rhubarb has broken down. Note; If you plan on using this as a sauce, you'll want the mixture a little runnier.
Carefully pour the mixture into sterilized canning jars leaving 1/2 inch room at the top. Store the jars in the fridge for immediate use or freeze for up to 6 months. If you prefer to make a shelf-stable jam, process in a water bath for 10 minutes.
Notes
Generally, 1 pound of rhubarb equals about 3 cups of chopped rhubarb. It makes a nice light meal and using chicken or vegetable broth and a little low-fat Greek yogurt to add creaminess helps keep the calorie count low.