I buy frozen rhubarb at my local Whole Foods. I put it in a bowl and microwave it for about 3 minutes. Then I put it in the blender with some WF blueberry or strawberry syrup (maybe 3 tbsp) and blend until its at a good consistency, really however you like it. I put it back in the bowl and sprinkle a packet of stevia over the top and BOOM. Tastes like fruit!
One bag of Rhubarb is a cup and a half and it makes a good bowl full! YUM!
Edit: I know there is a recipe out there where people used the oatmeal packet or the vanilla pudding packets and put it over the rhubarb and popped it in the oven. It turns it into a crumble. Sounds delicious