So, the second attempt turned out better. Firstly I grated the carrot rather than puréed it, secondly I beat the mixture as opposed to just stirring. This time I added the ginger. I also pulled the cake out of the oven a little earlier and the end result was a moister fluffier finish. I still used Truvia as that is what we have in the cupboard. Chose walnuts this time in preference to the icing carrot thingies. And this weekend the good NHS lady at our local surgery is making one too.