Wow, this was tart! I'm a bit confused about what it's actually supposed to be though. It wasn't quite concentrated enough to be a cordial, but we found it way too intense to drink straight. My husband mixed it, half and half with some American style lemonade and enjoyed it. This is more like a rhubarb juice. I think to achieve cordial, you'd need to cook the rhubarb, cloves, ginger, lemon juice, and more water than called for until the rhubarb was soft, then strain it and boil the remaining liquid down with some sugar, at least 150g, if not 200g. Sorry about the rating Luschka!