Place the sliced rhubarb into a solid steam tray along with sliced ginger, the ginger syrup and icing sugar. Do not cover. Place in steam oven for and cook on 100ºC for 4 minutes.
Place the crème fraiche in a bowl and sweeten to taste.
When the rhubarb is cooked drain the syrup into a saucepan and reduce by half on the hob. Leave to cool.