Cut the rhubarb into inch-long chunks and place in a pan with the water and golden sugar.
Cook over a low-medium heat for approximately 10 minutes, stirring occasionally and gently until the rhubarb is just tender (you can add extra water if it looks too dry during cooking). Transfer to a bowl to cool.
To make the custard, in a large bowl whisk the sugar, eggs, cornflour and vanilla together until pale.
Heat the milk over a medium heat in a large pan until just beginning to simmer.
Pour the millk over the egg mixture, whisking well, then transfer back into the pan.
Stir gently over the heat until it thickens, then take off the heat, cover and set aside to cool a little.
Crush the biscuits roughly and use them to line the bottom of each serving bowl.
Top with the rhubarb, then the custard.
Leave to set for a few minutes, then top with three raspberries and a sprig of mint each.
Place in the fridge for an hour to set.
Easy rhubarb and custard pudding https://www.amummytoo.co.uk/easy-rhubarb-and-custard-pudding/